GLENDALE, Ariz. -- Every year, the majority of the best prospects in the Arizona Fall League are position players. Teams are reluctant to send blue-chip pitchers to the AFL if they've logged a full season of Minor League innings or sustained a serious injury during the season.
Glendale Desert Dogs right-hander Mitch Keller (Pirates' No. 2) missed five weeks in May and June with a back strain, while Scottsdale Scorpions righty Albert Abreu (Yankees' No. 7) lost most of June and July to a shoulder strain. They're both in Arizona to make up for some lost innings, and they faced off on Tuesday in one of the marquee pitching matchups of the still-young Fall League season.
• Gameday
Keller, the top-rated mound prospect in the AFL (No. 18 on MLBPipeline.com's Top 100), and Abreu, whose ceiling rivals that of any pitcher in a deep Yankees farm system, both lived up to their reputations. Keller allowed just one run in 3 2/3 innings while Abreu dominated with eight strikeouts in five scoreless innings. Both pitchers topped out at 98 mph with their fastballs in a game Scottsdale won 10-1 with nine runs in the top of the ninth.
Abreu, 22, signed with the Astros for $185,000 out of the Dominican Republic in 2013. He came to the Yankees last November in a trade for Brian McCann that also netted righty Jorge Guzman (whose fastball can reach 103 mph). He's a 6-foot-2, 175-pounder with a bit of a short-arm delivery that provides deception.

Abreu has the potential for three plus pitches, and all three were working against the Desert Dogs. Of his eight strikeouts, three came on fastballs, three on breaking balls and two on a changeup. He threw 33 fastballs, 19 for strikes, averaging 96 mph and never dipping below 94.
Abreu was very efficient at locating his secondary pitches, delivering 15 of 21 breaking balls and seven of nine changeups in the zone. He generated five swings-and-misses with breaking balls and four with changeups, compared to three with his fastball. He's known for throwing both a curveball and slider, and most of his 82-84 mph breaking balls against the Desert Dogs had curve shape.
Only Danny Mendick (White Sox) and Tyler Krieger (Indians' No. 19) managed hits off Abreu -- and Krieger's double might have been caught if left fielder Billy McKinney (Yankees' No. 23) had taken a more efficient route. Logan Hill (Pirates) managed a pair of walks but Abreu showed better control than might be expected for a pitcher who has averaged 4.2 walks per nine innings in the Minors.
Though he wasn't as spectacular as Abreu, Keller still showed why he's considered one of the best pitching prospects in baseball. A second-round pick in 2014 from an Iowa high school, he's the type of projectable prep arm that the Pirates have had success developing.

The 21-year-old Keller has an athletic delivery and generates a lot of life on his fastball down in the strike zone, making it difficult for batters to square up. He didn't consistently locate his fastball against the Scorpions, throwing just 28 of 46 pitches for strikes, but they couldn't do much with it. He sat at 94-96 with his heater, recorded both of his strikeouts with it and allowed just one hit -- a Brantley Bell (Reds) single -- on 10 balls in play.
Keller didn't use his secondary offerings much, throwing just eight curveballs (four for strikes) and six changeups (only one for a strike). He gets good depth on his curve, which ranged from 80-82 mph and could become a plus pitch, but he'll have to trust his changeup more in the future.