Knife Prank Aside, Naylor Is Marlins’ Best

BEST PLAYER: Low Class A Greensboro first baseman Josh Naylor has huge power, which earned him a $2.2 million bonus as the 12th overall pick in the 2015 draft.

Listed at 6 feet and 225 pounds, the lefty-swinging Naylor has drawn comparisons with Prince Fielder for his thick body and raw strength. He hit .256/.320/.426 with 22 extra-base hits, including seven home runs, and 38 RBIs through 58 games.

The Mississauga, Ontario, high school product stole nine bases in 11 tries, showing surprising speed for a big guy.

Though the 19-year-old Naylor’s future is bright, his immaturity could be an issue. Early in June, he engaged in what the Marlins described as a “prank” and accidentally stabbed teammate Stone Garrett with a knife. Garrett needed three stitches and follow-up surgery on his thumb.

Naylor was suspended for one game.

BIGGEST LEAP FORWARD: High Class A Jupiter righthander Luis Castillo has emerged this season despite not being regarded as a top prospect this spring.

With a fastball that has reached 101 mph, the 23-year-old Castillo now has the Marlins’ full attention. The Giants signed him out of the Dominican Republic in 2011, and the Marlins acquired him for Casey McGehee in December 2014.

Castillo, who has added a power changeup and a wipeout slider to form a three-pitch mix, began 2015 as a reliever at Greensboro but has thrived as a starter this season at Jupiter, going 5-3, 2.15 through 13 games with 45 strikeouts and 10 walks in 63 innings.

BIGGEST DISAPPOINTMENT: This season goes down as another lost one for 20-year-old righthander Tyler Kolek, the second overall pick in the 2014 draft. The Shepherd (Texas) High product recorded a 4.56 ERA at Greensboro last season, then lost a chance at redemption in 2016 when he had Tommy John surgery in April.

Scouting director Stan Meek said the organization still has faith in Kolek.

“The way they’re doing these surgeries these days, the chances of guys coming back as good as they were before—it’s a really good percentage,” Meek said.

“He is a great kid. This will actually let him mature mentally as he watches the game . . . He could go through (the system) pretty fast once he gets back from surgery.”