PORT CHARLOTTE, Fla. -- When healthy last season, Tyler Glasnow established himself as one of the best pitchers in the American League and a key part of the Rays’ rotation. Now he could be adding another pitch to his repertoire.

Glasnow -- who featured a four-seam fastball, curveball and changeup last season -- is ditching the changeup in 2020, and he is looking to replace it with a splitter. He has worked on it throughout the offseason, and he threw it a couple of times in his first bullpen session of the spring on Monday in Port Charlotte.

“It’s just something that I’ve been messing around with now,” Glasnow said. “I want to get a third pitch. I don’t know what it will be, but the splitter feels good right now."

Last season, Glasnow threw his four-seam fastball 67.6 percent of the time and finished in the 95th percentile in velocity. The fastball helped set up his curveball, which ultimately became his go-to secondary pitch, throwing it 29.1 percent of the time and also ranking in the 95th percentile in spin.

The four-seam and curveball combination proved to be effective for Glasnow, who finished with a 1.78 ERA in 12 starts last season, but he would occasionally throw the changeup to mix speeds.

Glasnow was effective with the changeup, limiting hitters to a .125 batting average, though it came in a small sample size as he threw the pitch just 32 times last season. The effectiveness of the pitch, however, wasn’t the issue for him. Due to some mechanical issues, Glasnow began to feel some discomfort when throwing the pitch, and he landed on the 60-day injured list on May 11 with a mild right forearm strain.

“[The changeup] was a pitch I kind of featured, and I just kind of started throwing it during throwing programs and I was like, ‘Whatever, I guess I’ll throw it in a game,’ and it felt amazing,” Glasnow said. “But when I looked back at video, I was kind of dropping down a little bit … and that’s like a big no-no.”

Establishing a splitter, which should help his pitch mix, isn’t the only thing Glasnow will be working toward this spring. The righty has struggled with tipping his pitches at times throughout his career, including in Game 5 of the AL Division Series against the Astros.

“I probably think I’ll be able to address it during the season,” Glasnow said. “I’ll be more conscious of it to where like inning-to-inning, I’ll just be able to have a coach letting me know if I’m doing something different, so now I kind of have it in the back of my mind.”

Staying healthy will also be key for Glasnow, who is expected to be a big part of the Rays’ rotation in 2020. Despite undergoing a “really, really minor” wrist surgery in November, Glasnow feels “100 percent” entering Spring Training.

“Just two weeks after [the surgery], I was already lifting and throwing,” Glasnow said. “I’ve already thrown a couple [bullpen sessions], and I feel really good.”

New jersey numbers

Newly acquired first baseman and designated hitter José Martínez, who attended Monday’s optional workout, will wear No. 40 with the Rays. Brian O’Grady, who was acquired from the Reds, also attended Monday’s workout and will wear No. 31. Other new faces (and numbers) in the clubhouse include Hunter Renfroe (No. 11), Lucius Fox (No. 19), Vidal Brujan (No. 22), Kevin Padlo (No. 37), Kevan Smith (No. 44), Ronaldo Hernandez (No. 55) and Randy Arozarena (No. 56). Manuel Margot, who was acquired from the Padres on Saturday, will wear No. 13.

Inside the Spring Training clubhouse, Brandon Lowe took over Matt Duffy’s old locker, while Diego Castillo and Yonny Chirinos moved their lockers to the far corner, joining Willy Adames, Yandy Díaz, José Alvarado, Martínez, Arozarena and Brujan.