GLENDALE, Ariz. -- A starting pitcher throughout his amateur and pro career, Tanner Houck moved to a bullpen role in Triple-A in mid-July. After returning to the rotation in the Arizona Fall League, he battled his command in his first two outings before turning in one of the best starts the developmental circuit has seen this year.

Houck matched an AFL season high with eight strikeouts in just four innings of work on Wednesday afternoon, leading the Peoria Javelinas to a 2-0 victory over the Glendale Desert Dogs. Forrest Whitley (Astros) and Daniel Lynch (Royals), who, like Houck, were drafted in the first round, fanned eight in Fall League games last week.

Houck yielded six runs (four earned) with just three strikeouts in 5 1/3 innings over his first two AFL starts but looked much sharper in his third. He worked up to 95 mph with his four-seam fastball and in the low 90s with his two-seamer, and his best pitch gave Peoria fits. Six of his strikeouts came via his slider, which sat at 84-86 mph.

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"I was really able to command the slider on top of the two-seam, four-seam and changeup," said Houck, the 24th overall pick in the 2016 Draft out of the University of Missouri. "I was dealing with four pitches today. Just one of those days that everything was clicking."

Fellow Javelinas right-hander Bryan Mata and Houck are Boston's two best pitching prospects. Though they moved him to the bullpen in Triple-A to position him for a possible late-season callup, the Red Sox plan on keeping Houck in the rotation. Some scouts have questioned whether his low arm slot is conducive to starting, though the same questions existed about Chris Sale, and Boston officials aren't concerned.

The key for the 23-year-old going forward will be to refine his changeup, which is his top priority in the AFL. He uses a circle grip across four seams, throwing it harder than most in the upper 80s and prioritizing action over velocity separation from his fastball.

Left-handers have hit .278 against Houck the last two seasons -- compared to .223 by righties -- and a better changeup will help him keep them in check. He was able to dominate with a combination of a heavy sinker and a slider as an amateur, and he said he has had to force himself to use the changeup more often since turning pro.

"It's a pitch that I didn't use in college very much," Houck said. "When you get in pro ball, if you want to be a starter, you've got to throw a third or fourth pitch. For me, that's definitely the changeup. I've been working on it all season and having a lot of feel for it. I flashed it a few times here today."

The Desert Dogs managed just five hits and struck out 16 times against Houck and four relievers. Third baseman Elehuris Montero (Cardinals) served as their their lone offensive bright spot with two hits, including a triple off Houck.

Right fielder Jared Oliva (Pirates) walked three times for the Javelinas and scored the game's first run in the top of the first on an RBI single from DH Jarred Kelenic (Mariners). The only other run came on a fourth-inning homer by second baseman Owen Miller (Padres), a 417-foot blast to left-center with an exit velocity of 102 mph against left-hander Bernardo Flores (White Sox).

Peoria improved to 7-5 with the victory, climbing to within 1 1/2 games of first-place Surprise in the West Division. Glendale's fifth straight loss dropped its record to 3-9, the worst in the league.