Pitcher Corey Kluber takes part in a drill during Texas Rangers spring training on Feb. 14, 2020. Charlie Riedel/Associated Press

The level of interest in free-agent pitcher Corey Kluber remains unclear, but the Red Sox are doing their due diligence.

Boston was one of the teams to attend Kluber’s showcase on Wednesday in Florida, a source confirmed to the Boston Herald. The two-time Cy Young winner threw a bullpen session in front of representatives from reportedly about 25 teams at the Cressey Sports Performance facility in Palm Beach Gardens, Florida, as he looks to sign with a team after two lost seasons due to injury.

Kluber was joined by free-agent relievers Steve Cishek and Anthony Swarzak, who the Red Sox also watched. The three pitchers are represented by the same agency, Jet Sports Management.

According to ESPN’s Jeff Passan, scouts came away “impressed” by Kluber’s bullpen session, in which he threw 30 pitches. His fastball sat at 88-90 mph and he also showed a few off-speed pitches.

Kluber, who turns 35 in April, was traded from Cleveland to the Rangers last year but made just one start in 2020. He left his debut after one inning with a torn teres major muscle in his right shoulder. He missed most of the 2019 season after he fractured his right arm.

Kluber has made just eight starts and thrown 36 2/3 innings over the last two seasons, and he said in a recent interview with ESPN that the workout was mostly to show teams that the injuries were behind him.

“I don’t have a mindset that I need to prove myself to anyone, so to speak,” Kluber said. “I just need to show people that I’m healthy. I’m not putting pressure on myself to go out there and do X, Y and Z. It’s just about showing teams I’m progressing through a normal offseason.”

Kluber has been living and training in Winchester, Massachusetts, where his wife Amanda is from, during every offseason since 2016. His trainer, Eric Cressey, also has a facility in Hudson, Massachusetts, but they opted to do the workout in Florida because of lighter restrictions during the pandemic.

But his familiarity with Massachusetts, where he and his wife continue to raise their children, certainly doesn’t hurt the Red Sox’ chances of landing him. The Yankees, Mets, Rays and Blue Jays are also among the many teams reportedly at Wednesday’s workout.

Kluber spent nine seasons with the Indians, where he was one of the most dominant pitchers in baseball. He won the Cy Young in 2014 and 2017, and finished third twice, including in 2018, his last full season in the majors when he went 20-7 with a 2.89 ERA and 222 strikeouts.

THE RED SOX are among the teams who “have been involved to some extent in negotiations” free agent Marcus Semien, The Athletic’s Jim Bowden reported Wednesday. The Phillies, Reds and Athletics also have been involved, Bowden noted.

The 30-year-old shortstop would play second base if Boston signed him, and Peter Gammons of The Athletic reported last month that the Red Sox “like” Semien.

Semien struggled during the shortened 2020 season, hitting just .223 with seven home runs and 23 RBI. He finished third for the 2019 AL MVP voting when he batted .285 with a 33 home runs and 92 RBI for Oakland.

The Red Sox finished 20th in slugging percentage (.356) from the second base position in 2020. They finished tied for 21st in home runs (5) and tied for 22nd in doubles (11) at second base.

“We definitely have some options internally (at second base),” Red Sox GM Brian O’Halloran said in December. “But we’re also open-minded. And this is not exclusive to second base. We’re open minded to different ways of improving the club.”

Other free agent options include DJ LeMahieu, Jedd Gyorko, Kolten Wong, Kiké Hernandez, Tommy La Stella, Hanser Alberto and Jonathan Schoop. The Red Sox were known to be one of the teams interested in free agent second baseman Ha-seong Kim who ended up signing with the Padres.

Christian Arroyo, Michael Chavis and Jonathan Arauz are among the internal options.