JUPITER, Fla. -- Marlins left-hander ?Trevor Rogers? might have been last year's National League Rookie of the Year runner-up, but he's certainly not resting on his laurels.

Rogers knew that if he wanted to take his game to another level, he would have to improve his slider. Predominately a fastball/changeup pitcher, Rogers turned to his slider 14.8 percent of the time in 2021, allowing a .273 average and an expected slugging percentage of .452 in 44 at-bats. Though his third offering was improving, it wasn't where he needed it to be.

Rogers spent the past month and a half playing around with the new grip, but he finally had a chance to test it out on Sunday afternoon against Triple-A Nationals hitters on a back field at the Roger Dean Chevrolet Stadium complex. Across two innings, he threw the slider seven times. The pitch showed nice sweeping action late, with good pace and break. Overall, Rogers allowed a solo homer and struck out two looking. Of his 30 pitches, 19 were for strikes. His fastball velocity ranged from 94-96 mph.

"Just listening to him talk with [pitching coach Mel Stottlemyre Jr.], I felt a little antsy in the first, but you guys heard me talking enough about these first outings -- get them out there, get them in against somebody else, start to get the process," manager Don Mattingly said. "Trev's a lot further along than in the past. He's got a purpose. What he's wanting to do with his slider right now, what he's trying to do with his fastball right now, knowing that all these pieces are going to start fitting together."

A year ago, Rogers was vying for a spot in the rotation after experiencing mixed results (6.11 ERA, 12.5 K/9) upon his MLB debut in 2020. By season's end, he paced all NL rookie pitchers in categories like ERA, innings and strikeouts.

Unfortunately, due to the way the Grapefruit League schedule lines up, Rogers' day to pitch comes on the club's off-day. So Rogers will continue to fine-tune his slider on the back fields. It's a step up from throwing every day with his old high school catcher in Carlsbad, N.M., or off the fence of his backyard.

"I try to approach it the same that I still have a spot to earn on this team," Rogers said. "If I don't look at it that way, I think complacency leaks in. This organization's too loaded with arms for me to get complacent. So I've got to come out and dominate and compete every day to make sure that spot's mine. I know there's a lot of guys behind me hungry to be in the big leagues where I am. I'm just trying to make sure that spot's mine and keep it that way."