But there is no question what's been a big key to Pettit's success this year -- his changeup. It's truly become the left-hander's out-pitch, keeping opposing batters off-balance and giving Pettit an edge that pitchers love to have.
"He's got a Major League changeup," said Frederick pitching coach Blaine Beatty. "He's got a great feel for it, and he's not scared to use it. Even if it's not a good location -- it's always moving."
Pettit won his first four starts with Frederick and now has allowed only nine runs in 45 2/3 innings. He's struck out 33, walked only 11, and opposing hitters have a less-than-impressive .221 batting average against him so far. Pettit threw six shutout innings Monday night against Kinston but came away with a no-decision.
Both Beatty and Pettit agree that the pitcher's confidence in the changeup, and the fact that he's not afraid to throw it at any time, can be a big advantage. He'll throw it with the count 3-0 or 0-2, keeping hitters off-balance.
"It's just right there for me," Pettit said. "Anywhere I need to throw it, [I can]. I've got a lot of confidence in it right now."
Pettit also throws a fastball, curve and slider. His fastball stays around 90-92 mph, but Pettit said he's got better command of that this year as well. He's working on improving the curve.
But the changeup remains the key, and the pitch has gotten better in the last year. Interestingly, there hasn't been one major adjustment that suddenly gave Pettit a great changeup. He just refined some things, adjusted his mechanics and the pitch fell into place.
"Something just clicked," Pettit said. "Last year, I could throw it, but it was kind of hit-or-miss. This year, it's more of a feel thing. It just feels good in my hand."
Pettit pitched at Western Oregon University and was picked in the 42nd round of last year's Draft. He's been moving up the Minor League ladder quickly. He went 3-5 with a solid 2.61 ERA last year with two teams in 12 games. Pettit made the South Atlantic League All-Star Game this season with Delmarva, finishing with a 5-4 record and a 4.42 ERA before joining Frederick.
Pettit said he's enjoyed coming to Frederick since the Keys are having such a big year. They won the Carolina League's first-half Northern Division title and are poised to do the same in the second half.
Pettit has been a big reason the Keys have fared so well in this half. Opposing hitters are making all kinds of adjustments to figure out what Pettit does, but they haven't solved the puzzle just yet.
"He has a good feel for his stuff," Beatty said. "He doesn't fall into any patterns. He's a pitcher."
The races: Frederick has a 3 1/2-game lead over Kinston in the Northern Division with just less than two weeks left. Kinston holds a 1 1/2-game edge over Winston-Salem in the Southern with a game in hand.
Bad luck: Jesus Aguilar of Kinston homered twice and drove in six runs Friday, but it wound up being in a losing effort. Aguilar blasted a grand slam and a two-run homer, but Myrtle Beach topped Kinston, 15-9.
Team effort: Lynchburg got help from the entire lineup in Sunday's 12-1 rout of Frederick. All nine players either drove in or scored. In fact, eight players had at least one RBI.