Grasshoppers' Kolek delivers sizzling start

Tyler Kolek's right arm packs some serious heat. Now he's learning to control it.

The Marlins' top prospect allowed one hit and walked two with five strikeouts over a career-high six innings Monday as Class A Greensboro fell to Delmarva, 3-2, in walk-off fashion at Arthur W. Perdue Stadium.

"I got ahead of hitters," the 19-year-old said. "Normally I would have a lot of full counts, deep in the counts. Then my pitch count gets up and I wouldn't be able to go longer innings. I kept it shorter today and it felt good. I had good command of the fastball and got guys out early."

Kolek leaned on his trademark fastball, a powerful pitch that consistently sits in the mid-90's and has at times reached triple digits. According to the right-hander the important thing was to keep the pitch down, a technique he began to figure out during a series of successful bullpen sessions this past week.

"Our bullpens have been really great lately," Kolek said. "Just powering the fastball down, whether it's in or out or over the plate, doesn't really matter. Just getting the fastball down and then just straight to the secondary, and that's really what I've been trying to work on this season.

"Down in the zone. Pounding the fastball down. It's just a harder pitch to hit, so that's just something we've been working on for a while now. I think it's finally starting to come around."

To do so, the second overall pick in the 2014 Draft has occasionally had to ease back on his pitch speed a bit, though he doesn't get himself overly concerned with velocity.

"Most of the time if I start off throwing hard in a game I'll leave a lot of balls up," Kolek said, "and so I'll have to just tone that down and get confident in my fastball again and then I can put some effort into it and it'll be harder. It's something I don't really worry about. I'm going to throw as hard as I can throw that day and that's that. You know, there's no point in worrying about it."

MLB.com's No. 19 overall prospect retired nine of the final 10 batters he faced, with both walks coming in the first two innings. Kolek -- who has issued free passes to 36 batters in 75 innings this season -- acknowledged he is still working on his command. However, after walking seven batters in his last two starts, he could sense some improvement Monday.

"The two guys that I did walk, one of them I just walked him on a 3-2 count, but the other guy I should have never got to it," said Kolek. "But I'm really starting to feel better and so I'm pleased with that."

The Texas native added he has also progressed with his secondary pitches. While those offerings, which include a slider and changeup, are not at the same comfort level as his fastball, Kolek said he has been looking to implement them more in his outings.

"The first or second inning or so I'll rely on the fastball, getting it down, getting them to hit some ground balls," the 6-foot-5 hurler said. "Just feeling my way through the lineup, and then once they come around again, I'll go to an off-speed pitch. I've been working on my slider recently. It's been a great pitch, so I've been using it more."

Ultimately, the only disappointment Kolek felt after the start -- aside from the Grasshoppers' loss -- was that it couldn't continue.

"I was hoping they would," Kolek said. "But I guess my pitch count got up a little bit. It's been the longest I've went this year. I guess I'll have to wait until next time."

The Shorebirds rallied in the bottom of the ninth against Greensboro reliever Sam Alvis (3-4). Yermin Mercedes belted a two-run triple and Elier Leyva won the game with a sacrifice fly.

Garrett Cortright (3-1) got the win with two scoreless innings of relief for Delmarva. He didn't allow a hit and fanned three.