As a companion piece to last week's look at the hottest-hitting prospect in each organization, we present each system's pitching prospect who is performing the best down the stretch. There are some big names here, including three Top 100 Prospects, but 15 of the arms noted below rank in the bottom half of our team Top 30 lists -- and right-hander Adam Oller hasn't quite cracked our Mets Top 30.
AMERICAN LEAGUE EAST
Blue Jays: Zach Logue, LHP (No. 28)
The 25-year-old left-hander started showing added velocity in the 92-93 range and added a cutter in 2021. Those improvements not only earned him a spot on the Top 30, but they're helping him finish strong at Triple-A Buffalo. Logue owns a 2.97 ERA with 37 strikeouts and seven walks in his last eight starts (39 1/3 innings), dating back to July 28. He should enter next spring with a chance to be more than mere organizational starting depth.
Orioles: Grayson Rodriguez, RHP (No. 2/MLB No. 8)
The top pitching prospect in baseball continues to do top-pitching-prospect kinds of things, with a 3.04 ERA, 0.97 WHIP and a 14.1 K/9 rate over his last five starts as a 21-year-old in Double-A. Perhaps he’s saving his best for last as his first start this month, on Sept. 3, was a five-inning, one-hit shutout affair with seven strikeouts.
Rays: Seth Johnson, RHP (No. 16)
Tampa Bay sent the 2019 40th overall pick to Low-A Charleston for his first full season because of his brief resume on the mound. (He spent his first two years of college as a shortstop.) He is certainly building that resume now. Johnson hasn’t allowed more than one earned run in any of his last seven appearances with the RiverDogs, posting a 0.55 ERA with 46 strikeouts in 33 innings over that span. A 22-year-old is indeed old for Low-A, but this is a solid foundation on which the right-hander is building his career.
Red Sox: Wilkelman Gonzalez, RHP (No. 14)
Gonzalez is putting the finishing touches on a breakout season in his U.S. debut, posting a 1.85 ERA with 25 strikeouts in 24 1/3 innings since August began, including allowing just one earned run in his first two starts (9 2/3 innings) at the Low-A level. Signed for $250,000 out of Venezuela in 2018, he owns a lively mid-90s fastball and flashes a plus curveball and changeup. He has an overall 4-2 record with a 3.02 ERA, 54/11 K/BB ratio and .209 opponent average in 44 2/3 innings, mostly in Rookie ball.
Yankees: Randy Vasquez, RHP (No. 20)
A signee at $10,000 out of the Dominican Republic in 2018, Vasquez reportedly was included in the initial version of the Joey Gallo trade with the Rangers in July but stayed put when the deal was completed. He has permitted just four earned runs in six starts since the Trade Deadline, logging a 1.02 ERA with a 49/8 K/BB ratio in 35 1/3 innings. He might have the best curveball in the Yankees system, and he sets it up with a 93-96 mph fastball. That combination helped him post a 7-4 record with a 2.14 ERA, 124/34 K/BB ratio and .215 opponent average in 96 2/3 innings while rising from Low-A to Double-A.
AMERICAN LEAGUE CENTRAL
Indians: Xzavion Curry, RHP (No. 30)
Curry hasn't allowed a run in his last three starts, covering 16 innings, and has a 1.35 ERA with nearly twice as many strikeouts (27) as baserunners allowed (17) in 20 frames in High-A over the last month. He succeeds by relying heavily on a low-90s fastball, which can tick up to 96 mph and has good carry up in the strike zone, and backing it up with an average-ish group of secondary pitches highlighted by a low-80s slider. A seventh-rounder from Georgia Tech in 2019, he has gone 8-1 with a 2.01 ERA, 115/14 K/BB ratio and a .183 average in 89 1/3 innings between Low-A and High-A in his first full pro season.
Royals: Jon Heasley, RHP (No. 14)
A ton of the focus in the Royals system has been on the burgeoning bats, but don’t sleep on Heasley and his sprint to the finish. The 24-year-old right-hander owns a 1.45 ERA with 42 strikeouts and six walks allowed in his last six starts (31 innings) for Double-A Northwest Arkansas. Heasley possesses two above-average pitches in his fastball and curveball, and while control hasn’t typically been an issue, he is thriving by hitting the zone consistently down the stretch.
Tigers: Joey Wentz, LHP (No. 13)
Remember him? Wentz was in a Double-A Erie rotation alongside Casey Mize, Tarik Skubal and Matt Manning in 2019 but fell behind the others after undergoing Tommy John surgery a year later. He’s back and healthy at Double-A now and seems to be finding his own form in the final weeks of the season. Wentz owns a 2.70 ERA with 24 strikeouts in his last five starts (23 1/3 innings). He is sitting on 72 frames for the season heading into the season’s final weeks.
Twins: Joe Ryan, RHP (No. 6)
Ryan was dealt to the Twins from the Rays in the Nelson Cruz trade, but he didn’t make his organizational debut until Aug. 20 because he was pitching for Team USA in the Olympics. He’s worked 21 innings since, allowing just five earned runs (2.14 ERA), nine hits and three walks (0.57 WHIP) while striking out 26. What makes that more impressive is that two of his four Twins starts have come in the big leagues, including a seven-inning, one hit, no walk gem on Wednesday for his first Major League victory.
White Sox: McKinley Moore, RHP (No. 25)
Moore didn't win a game and posted a 7.95 ERA in three seasons at Arkansas-Little Rock before the White Sox drafted him in 2019's 14th round, and he continued to battle the strike zone early in his pro career. After posting a 5.53 ERA in his first 24 appearances this year, he has allowed just two runs with a 14/1 K/BB ratio in 10 innings during the last month. Armed with a 93-98 mph fastball and a mid-80s slider, he has a 4.54 ERA with eight saves and 56 strikeouts in 37 2/3 innings between Low-A and High-A.
AMERICAN LEAGUE WEST
Angels: Davis Daniel, RHP (No. 21)
Daniel had Tommy John surgery during his Draft year in 2019 and, because of that and the cancellation of the 2020 Minors campaign due to COVID-19, 2021 is his first season of pro competition. He’s made the most of it, pitching his way from High-A to Double-A and throwing well at both levels. That’s been particularly true of late, with a 2.61 ERA and 0.77 WHIP over his last four starts and an absurd 30/3 K/BB ratio over 20 2/3 innings in that span.
Astros: Chayce McDermott, RHP (No. 17)
A supplemental fourth-round pick out of Ball State in July, McDermott didn't make his pro debut until Aug. 13 and has breezed with a 1.72 ERA, .118 opponent average and 30 strikeouts in 15 2/3 innings, mostly in Low-A. The younger brother of NBA forward Sean McDermott, Chayce can hold mid-90s fastball velocity deep into games while topping out at 98 and also shows glimpses of a plus curveball.
Athletics: Colin Peluse, RHP (No. 18)
A ninth-rounder from the 2019 Draft, Peluse just got bumped up to Double-A, where he tossed five shutout innings and allowed just one hit and walked none while striking out eight in his debut at the level on Sept. 4. That capped off a stretch in the last month which saw him post a 27/3 K/BB ratio in 21 2/3 IP over five starts, with a 3.32 ERA and 0.78 WHIP.
Mariners: Matt Brash, RHP (No. 10)
Brash has been raising his profile all year, his first with the Mariners since coming over from the Padres at the 2020 Trade deadline. His most recent start, last Thursday, was a beaut -- six innings of no-hit ball with one walk and 11 strikeouts -- and he’s posted a 1.16 ERA, 0.60 WHIP, and a 15.4 K/9 in his last four starts, covering 23 1/3 IP. He’s been better in Double-A than he was down a level and overall now has a 2.08 ERA, .172 BAA and 13.7 K/9 rate in 2021.
Rangers: A.J. Alexy, RHP (No. 22)
Alexy hasn't allowed a run in any of his four starts (21 innings) during the last month, and he became the first player in MLB history to go five-plus scoreless innings while allowing one or fewer hits as a starter in each of his first two appearances. Part of the Yu Darvish trade with the Dodgers in 2017, he can touch 100 mph with his fastball and features high spin rates on his heater and 12-6 curveball. Before breaking into the big leagues with a bang, he compiled a 3-1 record with a 1.66 ERA with a .175 opponent average and 76 strikeouts in 65 innings between Double-A and Triple-A.
NATIONAL LEAGUE EAST
Braves: Bryce Elder, RHP (No. 11)
The Braves went over slot to keep Elder, their fifth-round pick in 2020, from returning to the University of Texas for his senior season. It’s looking like money well spent as the right-hander has pitched across three levels and up to Triple-A this year, with a combined 10.3 K/9 rate, a .210 BAA and a 3.09 ERA. Even as he’s adjusting to the highest level, he’s managed a 2.91 ERA and an 11.2 K/9 rate over the past month, with six innings of shutout ball with nine K’s kicking that stretch off and catapulting him from Double-A to Triple-A.
Marlins: Eury Perez, RHP (No. 6)
There aren't too many 6-foot-8 guys or 18-year-olds with the pitchability of Perez, who fills the zone with a three-pitch arsenal that includes a projectable 91-97 mph fastball, a solid curveball and a promising changeup. Signed for $200,000 out of the Dominican Republic in 2019, he opened eyes during instructional league last fall and has continued to do so in his pro debut, posting a 2-4 record with a 1.70 ERA, 100/24 K/BB ratio and .157 opponent average in 69 innings between Low-A and High-A. In five starts since August began, he has surrendered just three earned runs and allowed 16 baserunners while fanning 34 in 21 innings.
Mets: Adam Oller, RHP (unranked)
Yes, we’re trying to keep this list to Top 30 prospects, but Oller (who would slot in the 31-33 range right now for New York) has been too good of late to keep off. Dating back to July 23, the 26-year-old right-hander has put up a 0.44 ERA with 57 strikeouts in his last seven starts (41 innings) split between Double-A and Triple-A. In case anyone thinks those numbers are because the bulk of that work has come at the lower level, Oller has been even better at Syracuse, where he owns a 0.39 ERA through his first four starts. Acquired in the Minor League phase of the 2019 Rule 5 Draft, Oller has impressed the Mets with an improved changeup and with the way he mixes his stuff.
Nationals: Evan Lee, LHP (No. 22)
An outfielder and reliever in college prior to the 2018 Draft, the Arkansas product has taken real steps forward as a starter at High-A Wilmington in the back half of the 2021 season. Lee has surrendered one earned run or fewer in five of his last seven appearances, earning a 2.40 ERA in that 30-inning span. His 42 strikeouts since the start of August are the fourth-most at High-A, only one back of three hurlers in a tie for first.
Phillies: Kyle Dohy, LHP (No. 27)
While Dohy has struggled to establish himself in Triple-A, the left-handed reliever is showing that he can dominate in Double-A, even in hitting-friendly Reading. Over the last month, he’s posted a 1.69 ERA and 0.75 WHIP in 10 2/3 IP, walking only three and giving up five hits while whiffing 18. He hasn’t allowed a run in his last five outings, a stretch spanning 6 1/3 innings, during which he gave up just three hits and two walks while striking out 11. Combined in 2021, hitters have managed just a .184 BAA against him.
NATIONAL LEAGUE CENTRAL
Brewers: Aaron Ashby, LHP (No. 8)
The 23-year-old southpaw has bounced between Triple-A and the Majors since the start of August and played different roles along the way. He has thrived at both stops with a combined 1.37 ERA and 31 K’s in 26 1/3 innings in that time. His last four appearances have come with Milwaukee, and a 2.70 ERA and 0.75 WHIP over that span should keep him getting looks in The Show. Ashby’s slider has been particularly tough in the Majors; he has given up just one hit in 22 at-bats on the breaking pitch so far, and it has a 44.7 percent whiff rate.
Cardinals: Matthew Liberatore, LHP (No. 2/MLB No. 50)
At just 21, Liberatore was always going to be young for Triple-A, and it’s been clear as the season has worn on that he needed some time to grow into the Minors’ top level. He fired off four straight quality starts for Memphis from Aug. 10-Sept. 1, and while his Tuesday outing ended that streak, he still has a 3.03 ERA with 31 strikeouts and only six walks in his last five outings (32 2/3 innings). Liberatore is the only pitcher aged 21 or younger to throw more than 65 innings at Triple-A this season; he’s thrown 104 1/3.
Cubs: D.J. Herz, LHP (No. 13)
Herz has emerged as one of the Cubs' best pitching prospects in his first full pro season, using a mid-90s fastball and sharp low-80s slider to go 4-4 with a 3.18 ERA, .152 opponent average and 113 strikeouts in 70 2/3 innings, mostly in Low-A. Signed for an over-slot $500,000 as an eighth-round pick from a North Carolina high school in 2019, he has struck out 29 in 18 1/3 innings with a 1.47 ERA in the last month, including eight whiffs without an earned run over five frames in his High-A debut last Saturday.
Pirates: Quinn Priester, RHP (No. 2/MLB No. 52)
Back in July, there was a little talk about Priester’s stuff regressing a bit, with the 2019 first-rounder not missing as many bats as expected. He must have heard that, because since then, he’s been on a tear. Over the last month, Priester has struck out 12.2 per nine, whiffing 38 in 28 innings over five starts while walking just six. That includes two double-digit strikeout efforts, and he was right around a 40-percent swing-and-miss rate in a majority of his last 10 starts.
Reds: Dauri Moreta, RHP (No. 28)
Moreta got to Triple-A in early July and he’s yet to give up an earned run. The right-hander has appeared in 20 games, spanning 22 2/3 innings and has yielded just two unearned runs on 11 hits (.136 BAA) while walking only four and striking out 18. He’s slid nicely into Louisville’s closer role, saving five out of six over the last month, and he now has a combined 0.73 ERA, 0.75 WHIP and .159 BAA across two levels in 2021.
NATIONAL LEAGUE WEST
D-backs: Brandon Pfaadt, RHP (No. 26)
The 2020 fifth-rounder out of Division II Bellarmine University has truly put himself on the map by climbing three levels in his first full season. Armed with a four-pitch mix, Pfaadt is set to close out strong with a 1.66 ERA and 49 strikeouts in 43 1/3 innings between High-A and Double-A since the start of August. That includes a four-run outing for Amarillo on Wednesday; otherwise the numbers would be even more stellar.
Dodgers: Gavin Stone, RHP (No. 28)
Stone made a successful transition from reliever to starter during the shortened 2020 college season at Central Arkansas, throwing a 13-strikeout no-hitter in his final outing before the Dodgers took him in the fifth round. Relying heavily on a fastball that averages 94 mph and touches 98 with a low release point and a difficult induced-vertical break, he has struck out 42 and walked just three with a 3.00 ERA in 24 innings over the last month. He also has three average secondary offerings, led by a mid-80s slider, and has gone 2-2 with a 3.78 ERA that belies his 131/23 K/BB ratio in 88 innings between Low-A and High-A in his pro debut.
Giants: Kyle Harrison, LHP (No. 5)
The best healthy high school left-hander in the 2020 Draft, Harrison signed for late first-round money ($2,497,500) in the third round and has seen his stuff improve since. He's working in the mid-90s and touching 98 mph with his fastball while flashing a plus slider and feel for a changeup. He has a 1.05 ERA with a .167 opponent average and a 47/9 K/BB ratio in 25 2/3 innings during the last month, improving his overall Low-A numbers to a 3-3 record with a 3.36 ERA and 149 strikeouts in 93 2/3 frames in his pro debut.
Padres: Steven Wilson, RHP (No. 21)
A pure two-pitch reliever, Wilson has been as reliable as they come out of the bullpen at Triple-A El Paso lately. He hasn’t issued a walk (while fanning 11) in his last six relief appearances, and if we push that sample back to his last eight games, he has a 2.13 ERA with 18 strikeouts and only three passes in his last 12 2/3 innings. Wilson’s 37.3 percent K rate is eighth best among Triple-A pitchers with at least 30 innings this season.
Rockies: Chris McMahon, RHP (No. 10)
The Rockies’ second-rounder in 2020 was getting stronger as his first full season wore on, posting a 3.09 ERA in five August outings, going six innings or more in four of them. He struck out 32 and walked seven over those 29 1/3 innings and has a nifty 109/28 K/BB ratio in High-A for the year.