Here's a look at top prospects to watch in today's Minor League action:
Hitter to watch: Tyler O'Neill (Mariners' No. 4)
Something seemed to click for O'Neill at last summer's Pan Am Games. He struggled to make consistent contact before playing for Team Canada, but that suddenly isn't an issue as the 20-year-old outfielder enters Wednesday riding a 14-game hitting streak, a 28-game on-base streak and sporting a .336 batting average. The 2013 third-round Draft pick also has continued to show power in his first Double-A stint, with six home runs and seven doubles. O'Neill is back in action at 12 p.m. ET on MiLB.TV again.

Pitcher to watch: Josh Hader (Brewers' No. 4)
There's a reason Hader, MLBPipeline.com's No. 57 overall prospect, has found himself part of two non-waiver Trade Deadline deals. Harder, part of the Carlos Gomez return from Houston, has been nothing short of dominant for Double-A Biloxi, sporting a 0.94 ERA in six starts. The tall left-hander has allowed zero runs in three starts and one in each of the other three while fanning 40 in 28 2/3 innings. His fastball consistently sits 94-98 mph, and if he hones his changeup to go along with his slider, he could make an impact out of Milwaukee's bullpen later this season. Hader leads Double-A Biloxi vs Jacksonville at 7:40 p.m. ET on MiLB.TV.

Duel of the day: Mark Appel (Phillies' No. 4) vs. Mike Clevinger (Indians' No. 7)
While Vincent Velasquez dominates in the Majors, Appel -- MLBPipeline's No. 66 overall prospect and another part of the Ken Giles haul -- is quietly impressing for Triple-A Lehigh Valley, sporting a 3-1 record and a 3.00 ERA in five starts. A change of scenery has apparently done wonders for the 2013 No. 1 overall pick.
Clevinger has re-emerged as a potential big league starting prospect after struggling with an elbow injury and a tight leash during his rehab with the Angels. Now in his third season with the Indians, Clevinger is 4-0 with a 3.03 ERA in six starts for Triple-A Columbus. He led all Tribe farmhands with 145 strikeouts a year ago, and he has fanned 29 in 29 2/3 innings so far this season. The two battle at 6:35 p.m. ET on MiLB.TV.

Wednesday's Top 100 prospect probables
No. 34 Carson Fulmer (White Sox's No. 1), Birmingham vs. Jackson (12 p.m. ET on MiLB.TV)
No. 48 Jeff Hoffman (Rockies' No. 4), Albuquerque at Salt Lake (12:35 p.m. ET on MiLB.TV)
No. 56 Tyler Jay (Twins' No. 3), Fort Myers at Bradenton (6:30 p.m. ET)
No. 63 Braden Shipley (D-backs' No. 1), Reno at Sacramento (3:05 p.m. ET on MiLB.TV)
No. 100 Justus Sheffield (Indians' No. 5), Lynchburg at Salem (7:05 p.m. ET)
More top prospect probables
Jaime Schultz (Rays' No. 19), Durham vs. Buffalo (AAA)
Taylor Guerrieri (Rays' No. 6), Montgomery vs. Tennessee (AA)
Rookie Davis (Reds' No. 12), Pensacola at Chattanooga (AA)
Adalberto Mejia (Giants' No. 10), Richmond vs. Harrisburg (AA)
Thomas Eshelman (Phillies' No. 15), Clearwater at Dunedin (A Adv)
Keury Mella (Reds' No. 6), Daytona vs. Brevard County (A Adv)
Jeremy Rhoades (Angels' No. 18), Inland Empire at Lake Elsinora (A Adv)
Yency Almonte (Rockies' No. 30), Mondesto vs. High Desert (A Adv)
Justin Steele (Cubs' No. 17), South Bend at Daytona (A)
Marcos Diplan (Brewers' No. 19), Wisconsin vs. Clinton (A)
Jake Woodford (Cardinals' No. 12), Peoria vs. Beloit (A)