"I'm working on my changeup a lot," Eovaldi said. "I'm hoping to be able to throw that for strikes more. I know last year, I started using my curveball more, and it helped me out tremendously. Being able to use my slider and fastball off my curveball helped me out."
When you throw as hard as Eovaldi, it is natural to rely so heavily on pure heat. According to FanGraphs.com, his fastball averaged at 96.2 mph, which placed him in the upper tier of all starters. Eovaldi's fastball maxed out at 100 mph in 2013.
Because his fastball is such an explosive weapon, Eovaldi used it to get ahead in counts, and conversely, when he was behind, he'd dial up the heat. He used it so often, his pitching patterns became predictable. Per FanGraphs.com, Eovaldi threw his fastball 70.6 percent of the time. As for his changeup? Just 1.7 percent.
Eovaldi is hopeful of commanding four pitches -- including his slider and curveball.
"Getting first-pitch strikes with my secondary pitches, and even when behind in the count, is going to be huge for me this year," Eovaldi said. "If I'm able to throw all four of my pitches for strikes, it will help me out a lot."
Marlins pitchers and catchers begin Spring Training workouts at Roger Dean Stadium in Jupiter, Fla., on Sunday. Eovaldi, who turns 24 on Thursday, is already in South Florida, taking part in the Marlins Ayudan Week.
Miami maintains that Eovaldi is one of the team's building blocks. He is projected as the No. 2 starter, behind Jose Fernandez, and the two have the raw talent to be one of the game's most overpowering tandems.
Fernandez's fastball hit 99 mph during his 2013 National League Rookie of the Year Award-winning campaign. His average fastball, as reported by FanGraphs.com, was 94.9 mph.
What set Fernandez apart last season was the command he showed on all four of his pitches. He also was more unpredictable, throwing his fastball 57.3 percent of the time.
For Eovaldi, refining his secondary pitches is a work in progress, but there is little disputing his untapped talent. In an injury-plagued 2013, he went 4-6 with a 3.39 ERA in 18 starts.
It was a painful season overall for the team, which lost 100 games. For Eovaldi, the season started with a lengthy stint on the disabled list.
After enjoying a strong Spring Training, Eovaldi was pegged as the No. 2 starter. But in his final Grapefruit League outing, he experienced some discomfort in his shoulder, and he informed the team that something wasn't right.
The Marlins played it safe and Eovaldi opened 2013 on the DL. Once healthy, he had to basically build back up again, and he didn't join the rotation until June 18.
"I feel that was a fluke," Eovaldi said of his injury. "I've never had that happen to me before, or even any tightness in my shoulder before.
"It was, honestly, the very last game of Spring Training. It got tight. I wanted to be safe, and say something."
Though the team called his injury shoulder inflammation, Eovaldi labels it biceps tendinitis, because the muscle runs into the shoulder area. Either way, he was sidelined for several months.
"I had to shut it down," Eovaldi said. "It took so much time, because I basically had to go through Spring Training all over again."