Twins prospect honing knuckleball in Arizona Fall League

October 12th, 2024

SURPRISE, Ariz. -- Only one pitcher in the Arizona Fall League features a knuckleball. It danced in Devin Kirby's Salt River Rafters debut on Friday, almost too much.

Kirby landed just 12 of his 31 knucklers for strikes, yet persevered nonetheless. The Twins right-hander entered with the bases loaded with Surprise Saguaros and none out in the bottom of the third and retired the next three batters in order, yielding only a sacrifice fly. He got himself into trouble with a pair of two-out walks and a double-steal in the fourth, then fell behind in the count to hot-hitting Royals No. 5 prospect Carter Jensen before getting out of the jam by using a 90-mph fastball to induce a flyout.

"It's definitely a learning curve here coming from Florida, where my hand was too wet and the ball would slip out," Kirby said. "Here, it's too dry, so I'm trying to find a middle ground to make my hand be able to grip the ball because I don't use my fingernails. I use my fingertips.

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"So if I have just my natural hand oil, it's good. The Arizona heat dries my hand out so much it was a little learning curve in the game. But I've always been a pitcher to get outs. I've never been too powerful, just get outs and put up zeroes."

Kirby began fiddling with a knuckleball at Ukiah (Calif.) HS, but he was primarily a fastball/slider pitcher at Santa Rosa (Calif.) JC and when he transferred to Connecticut. After missing 2021 following Tommy John surgery, he realized he no longer could supinate a slider. The Huskies didn't have a catcher who could handle his knuckleball, so he gutted through his final two seasons with fastballs and changeups.

Out of college eligibility, Kirby headed to the California Collegiate League because he wanted to continue playing. Connecticut pitching coach Joshua MacDonald urged Kirby to focus on his knuckler in the CCL and tipped off the Twins to keep an eye on him. He compiled a 1.93 ERA with 17 strikeouts in 14 innings for the Healdsburg Prune Packers, after which Minnesota signed him for $500 as a nondrafted free agent.

Kirby spent last summer and this season at the Twins' training base in Fort Myers, Fla., posting a 3.44 ERA with 68 strikeouts in 49 2/3 innings between the Rookie-level Florida Complex League and the Single-A Florida State League. He's 25 and Minnesota wants to accelerate his development, so they sent him to the AFL.

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Kirby says his three goals with the Saguaros are to throw his knuckleball 70 percent of the time, for strikes 50 percent of the time and to keep it above 78 mph. In the 11-10 loss to the Saguaros, he threw 76 percent knucklers for 39 percent strikes while averaging 75 mph.

None of Salt River's catchers -- Yankees No. 30 prospect Rafael Flores, Jose Cordova (Rockies) and Maxwell Romero (Nationals) -- have experience handling the pitch.

"It's fun because it's like I'm a new show that everybody wants to watch," Kirby said. "The catchers are scared of me at first, but they do a good job at catching. Instead of getting to the framing part, they have to just take it to the chest every time. There have been times where they tried framing it and it just hits them in the chest, so it's fun to see them adjust."

Kirby has sought advice from other knuckleballers. He has talked with Mickey Jannis, who pitched in the AFL in 2017 and one game with the 2021 Orioles, and texted with Tom Candiotti, who won 151 games in the Majors.

"I'm going to have Mickey come in and work with me in a bullpen," Kirby said. "Tom Candiotti gave me some good information, but lately the harder you throw the knuckleball, the better with more swing and miss and getting guys out. So that's why I'm leaning toward Mickey more because his is 78-80.

"I'm just trying to figure it out just as much as anybody else would since it's only been a year and two months of throwing it primarily."