SCOTTSDALE, Ariz. -- Coming off a couple tough outings, Jon Duplantier put his recent struggles behind him on Tuesday night with his best Arizona Fall League start.Duplantier, the D-backs' top prospect, racked up nine strikeouts and induced 19 swinging strikes over 4 2/3 innings as Salt River edged Scottsdale, 3-2, at
SCOTTSDALE, Ariz. -- Coming off a couple tough outings, Jon Duplantier put his recent struggles behind him on Tuesday night with his best Arizona Fall League start.
Duplantier, the D-backs' top prospect, racked up nine strikeouts and induced 19 swinging strikes over 4 2/3 innings as Salt River edged Scottsdale, 3-2, at Salt River Fields. He allowed two earned runs on six hits and issued one walk.
The nine strikeouts are the most by any pitcher in the Fall League this season and only one other player (Kyle Zimmer, 2014) in the past 10 years has struck out more batters in a single game (11).
The performance was a marked improvement for Duplantier after he had combined for six earned runs, nine hits and six walks over eight innings in his last two starts.
"Last start, in Mesa, I didn't have my best fastball command and we went away from the fastball -- wrongfully so -- and went with a lot of breaking balls," Duplantier said. "Then, in turn, the bad fastball command allowed them to get the bat on the fastball."
Commanding the heater wasn't an issue for the 23-year-old right-hander on Tuesday, however. He posted respective strike rates of 58 and 67 percent with his two- and four-seam fastballs, and together they netted him five whiffs, while accounting for 52 percent of his pitch usage in the outing. Overall, he threw 59 of 81 pitches for strikes.
"Today, the thought process was different … we wanted to attack with the heater," said Duplantier, MLB Pipeline's No. 80 overall prospect, about his game plan against the Scorpions. "My fastball command was a lot better, especially to the arm side, and that just opened everything up."
Duplantier's feel for his fastball, which topped out at 97 mph and sat 94-95, made his trio of secondary pitches all the more effective. Of his 19 swinging strikes, eight came on his low-80s curveball, five on his 85- to 87-mph slider and one via his changeup, a pitch he mixed in more the second time through the lineup.
"The slider was good, curveball was pretty good at times, and then when I did start throwing changeups, they were down or they were down and in," said Duplantier. "I think the fastball command opened up the door for everything else. It just so happened that the slider had good depth and was kind of hard and the curveball had some heat behind it."
Duplantier pitched around a two-out double as he struck out the side in the first inning and notched two more strikeouts in the following frame after yielding a leadoff double. He added another strikeout in the third inning and added a pair of whiffs in the fourth, albeit while allowing a pair of runs.
Reds No. 2 prospect Taylor Trammell (No. 17 overall) led off the inning with his second opposite-field double in as many at-bats off Duplantier and then advanced to third on a Heath Quinn single. Two batters later, Shed Long tagged him for 106.8-mph single off of Rafters shortstop Carter Kieboom's glove to plate both runners.
The Rafters, after pushing across a run in the first inning on Tyler Nevin's single, knotted the score in the sixth on Sam Hilliard's second AFL home run, a booming solo shot down the right field line that traveled 414 feet and had an exit velocity of 114.8 mph, the game's hardest-hit ball.
The teams remained tied until the eighth inning, when Salt River's Josh Fuentes scored the game-winning run on a wild pitch after the Rafters had loaded the bases via a leadoff double and a pair of two-out walks.
Both Fuentes and Hilliard, the Rockies' No. 9 prospect, finished the game 2-for-4 at the plate. Nevin (Rockies' No. 11) was 1-for-4, though each of the four balls he put in play had 100-plus-mph exit velocities (including three ranging from 104.5 to 104.8 mph).
Mike Rosenbaum is a reporter for MLB.com. Follow him on Twitter at @GoldenSombrero.