Ranked No. 38 on the Top 100, De Leon compiled just two strikeouts through the first two innings but missed more bats as he worked deeper into the game, striking out the side in the subsequent frame and then notching a pair of strikeouts in the fourth and sixth innings, respectively.
De Leon's 10-strikeout performance was his second in as many starts, and he's now accomplished the feat four times in his past eight turns for Oklahoma City. In his Minor League career, the 24-year-old right-hander has recorded double-digit strikeouts in 15 of 63 starts over parts of four seasons.
With a win on Monday, De Leon improved to 6-1 in 15 starts for Oklahoma City. He's posted a 2.86 ERA and a 0.98 WHIP in that span, with 98 strikeouts and 20 walks in 78 2/3 innings, all the while limiting opposing hitters to a .199 average.
The rest of the best performances from top prospects Monday
• Nos. 15 and 61 overall prospects Amed Rosario (Mets' No. 1) and Dominic Smith (Mets' No. 2) hit back-to-back home runs in the third inning to help power Double-A Binghamton past Hartford, 6-3. Overall, the duo combined to go 5-for-6 at the plate, with three extra-base hits, three RBIs and five runs scored.
• No. 50 overall prospect Nick Senzel (Reds' No. 1) tallied four RBIs and reached base four times in Class A Dayton's 11-10 win over Lansing. The 2016 No. 2 overall Draft pick finished the game 2-for-3, hitting a bases-clearing double and drawing two walks, to improve his average to .315 for the Dragons. He also scored the winning run in the bottom of the ninth, capping a seven-run comeback by Dayton.
• For a second straight outing, No. 72 overall prospect Brady Aiken (Indians' No. 2) allowed exactly one earned run on three hits with six strikeouts in five innings for Class A Short Season Mahoning Valley. The 20-year-old lefty is 2-4 with a 5.48 ERA on the season, but he's accrued 48 strikeouts and allowed just three homers in 37 innings.
• After hitting 29 home runs with Double-A Midland, A's No. 4 prospect Matt Chapman connected on his first home run for Triple-A Nashville in a 12-3 rout of Omaha. Jaycob Brugman (A's No. 22) turned in another big offensive performance, going 2-for-5 with a home run and four RBIs, giving him 20 hits in his past 44 at-bats.
• After allowing six earned runs and walking six in his last outing, Blue Jays No. 10 prospect Conner Greene rebounded to toss seven scoreless innings for Double-A New Hampshire and lower his ERA to 3.55. The 21-year-old right-hander scattered three hits, walked a pair and struck out one, with 54 of his 86 pitches going for strikes. It was his third scoreless start for the Fisher Cats.
"I have the same approach every outing," Greene told MiLB.com. "The six walks in the last outing, that was just a lack of command. I wasn't staying within myself and maybe a little overthrowing. My approach is the same every game, I try to change nothing day in and day out and try to compete and give my team a chance to win. Nothing much really changed, except I had fastball command, unlike last time, which was very bad.
"If I keep it low, it's a good outing. If I can spot up with the fastball, I throw with a little velo and the low fastball, good things happen. Overall, fastball down in the zone, I believe, is the key to a successful outing. And if you can do it every time, you can really get through lineups."
• Braves No. 13 prospect Austin Riley homered for a second straight game for Class A Rome on Monday, his 17th of the season. Riley's power really has been on display during the second half, during which he's connected on 14 home runs in 54 games.
• No prospect is swinging a hotter bat right now than Austin Slater. On Monday, the Giants' No. 22 prospect paced Triple-A Sacramento's offense in a win over Reno with a pair of two-run home runs and an RBI double, finishing the contest 3-for-5 with five RBIs. The 23-year-old second-baseman-turned-outfielder has collected at least three hits in four straight games for the River Cats, during which he's gone 13-for-17 to improve his Triple-A average to .297 from .258. He has four home runs, three doubles, nine RBIs and eight runs scored in that span.
• Rays No. 9 prospect Casey Gillaspie hit a pair of two-run homers and scored three times in a 4-for-5 performance for Triple-A Durham in a 10-6 win over Norfolk. The switch-hitting first baseman has gone deep four times in 33 games since being promoted from Double-A Montgomery, where he had 11 home runs in 85 games.
• Red Sox No. 21 prospect Bobby Dalbec fell a double shy of the cycle but extended his hitting streak to seven games with a 3-for-5 performance for Class A Short Season Lowell. The 2016 fourth-rounder's home run was his sixth of the season, while his three RBIs give him 25 through 23 games.
• Rockies No. 8 prospect Kyle Freeland held Reno to just one hit over seven innings in his second straight scoreless start for Triple-A Albuquerque. The 2014 first-rounder struck out four without issuing a walk and generated another 10 outs on the ground before departing the game after 91 pitches (59 strikes).
• With his pair of doubles for Class A Asheville, Rockies No. 29 prospect Brian Mundell is now tied for the South Atlantic League record with 55. The 22-year-old first baseman is having an impressive full-season debut, with a .322 average, 70 extra-base hits and 78 RBIs through 124 games.
• Yankees No. 13 prospect Dustin Fowler's bat proved to be the difference in Double-A Trenton's 5-2 win over Bowie as he finished a double short of hitting for the cycle. The 21-year-old outfielder notched his 10th home run, a solo shot in the first inning, as well as his 13th triple. He's hit 29 doubles and swiped 22 bags in 121 games.