JUPITER, Fla. -- At first glance, Tyler Kolek's mere size jumps out at you. The 6-foot-5, 260-pounder casts an imposing figure on the mound. Kolek may have the body type of an outside linebacker, but he throws a baseball about as hard as Reds flame-throwing closer Aroldis Chapman.
Minor League camp has opened for the Marlins, and one of the big attractions on the back fields at the Roger Dean Stadium complex is Kolek, the second overall pick in the 2014 First-Year Player Draft who once threw 102 mph in high school.
The big right-hander from tiny Shepherd, Texas, threw off the mound on Wednesday. He impressed.
"Tyler reported to camp in great shape, he looks tremendous," Marlins general manager Dan Jennings said. "He looks great in his bullpens."
At age 19, Miami's top prospect still needs to polish up his command and fine-tune his offspeed pitches. The pure power arm, however, is quite evident.
Kolek is entering his first full professional season. In limited games after signing last summer, he threw 22 innings for the Gulf Coast League Marlins and posted a 4.50 ERA.
"It's been a really fun experience," Kolek said. "I went through instructional league last year after the season. It's basically the same thing. There were fewer guys in early camp, so there was more one-on-one time, which was nice."
In the offseason, he worked several times a week with Miami's Minor League pitching coordinator Charlie Corbell, who lives in Texas.
"They ironed out a few things mechanically," Jennings said. "They did some work with his breaking ball, to add some quality to that. Right now, we're looking for him to come into this camp and continue the progression."
Kolek is phasing out his slider and relying more on a curveball.
The plan is for Kolek to start off at Class A Greensboro, where he will keep refining his offspeed pitches. The fastball is there. How quickly he gets his secondary pitches ready will determine how quickly he advances through the system.
"With him especially, the fastball has always been there," Jennings said. "He was able to reach back to 102 in high school. Special arm action. Special delivery and certainly a powerful body. Now, it's just about finetuning his breaking ball. We eliminated the slider and went with the curve. We think that will help him focus more on one pitch versus having two separate pitches. We think putting him in a league with guys his age should help benefit him."
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter @JoeFrisaro. This story was not subject to the approval of Major League Baseball or its clubs.