PITTSBURGH -- After being set back by Tommy John surgery in 2017 and neurogenic thoracic outlet syndrome in '19, Nick Burdi believed he was ready to establish himself as a late-inning reliever in '20.

Burdi had a strong preseason camp, struck out the side in his first appearance of the season then earned his long-awaited first save on July 28. He made only two more appearances before going on the 45-day injured list with what the Pirates initially called a “right elbow injury” and later referred to as a “significant” forearm strain.

As it turns out, Burdi was dealing with an injury that necessitated Tommy John surgery for the second time in his young career. The 27-year-old right-hander underwent the operation last month, and he will spend the entire 2021 season recovering.

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Facing Sunday’s deadline to activate players from the 60-day IL, the Pirates designated Burdi for assignment. If he goes unclaimed and clears waivers, he will become a free agent. In that event, the Pirates could re-sign him to a Minor League deal to help him through the lengthy rehabilitation process.

“There’s certainly plenty of examples of pitchers who have gone through significant injuries early in their career and then figure out a way to stay healthy and have a really good run of success,” general manager Ben Cherington said on Monday. “I think Nick is definitely capable of that. He’s obviously got really good stuff. He’s an incredibly hard worker. He’s really smart. He’s learning all the time. You add all that stuff up, and as much as it’s been frustrating for him to this point, I think all that gives him a chance to be a really good Major League pitcher.

“We’d love to continue working with him. It was just a matter of knowing he wasn’t going to be able to pitch next year and getting back to that focus of ours on just trying to build as much talent as we can into our 40-man [roster]. It was going to be really hard to keep him on that throughout the whole year. We’ll just have to see what happens with that. If circumstances allow and there’s a way to keep him in the Pirates organization -- help him through the rehab and get him back to the big leagues -- we’d be excited about doing that.”

The Pirates acquired the big-armed Burdi from the Phillies on Dec. 14, 2017, after Philadelphia selected him off Minnesota’s roster in the Rule 5 Draft. Despite only pitching in 16 Major League games, Burdi accumulated enough service time over the past three years to be eligible for salary arbitration this offseason and spent enough time on the Pirates’ active roster to shed his Rule 5 Draft restrictions.

On Aug. 12, Pirates director of sports medicine Todd Tomczyk said the club’s initial medical review determined that surgery was not immediately necessary for Burdi, but that update still came with some concern. Burdi had a platelet-rich plasma injection and was told not to throw for 10-12 weeks, and Tomczyk suggested that his injury included “some inflammation in the nerve” related to his bout with TOS.

Burdi’s surgery was performed by Dr. Keith Meister on Oct. 14, the team announced late Sunday afternoon. He is projected to return to full competitive baseball activities in 16-18 months.

Designating Burdi and declining Chris Archer’s club option for next season left the Pirates with five players on the 60-day IL -- Anthony Alford, Phillip Evans, Michael Feliz, Clay Holmes and Jameson Taillon -- and four open spots on their 40-man roster.

The Pirates reinstated all five players from the injured list on Sunday night and cleared the necessary space by designating reliever Dovydas Neverauskas for assignment. Their roster is now full at 40 players.

Given several opportunities to claim a job in Pittsburgh’s bullpen over the last three years, Neverauskas never delivered on the promise of the stuff he possesses. The hard-throwing righty had a solid showing as a rookie in 2017, recording a 3.91 ERA and 1.26 WHIP in 24 appearances, but he then logged an 8.13 ERA and 1.74 WHIP in 52 appearances from '18-20.

Neverauskas, the first Lithuanian player in Major League history, put together a 7.11 ERA while allowing five homers in 19 innings this season. The 27-year-old pitched only once over the final two weeks of the season, indicating that he had finally fallen out of management’s favor.

"He's got good stuff. Obviously, the curveball is really good,” Cherington said. "He just hadn't gotten to a point yet where he really figured out how to use the fastball effectively at the Major League level, even though the velocity's good."

Cherington revealed Monday that Neverauskas, who is out of Minor League options, has “mutual interest” in signing with a team overseas. That played a part in the Pirates’ decision to remove him from their roster.

Alford, a candidate to start in center field next year, was sidelined in early September by a right elbow fracture. Evans, a super-utility man who got off to a strong start at the plate, missed most of the season due to a concussion and broken jaw he sustained in an early August collision with Gregory Polanco.

Like Burdi, Feliz and Holmes were expected to play important roles in the bullpen this year, but they were out nearly the entire season due to sprained right elbows. Cherington said Monday that the Pirates “don’t have any reason to believe they won’t be ready to go” in terms of health next season.

Taillon, who had his second Tommy John surgery on Aug. 13, 2019, spent this year rehabbing. He is expected to be ready for Spring Training, and the Pirates are optimistic that the hard-working right-hander will claim a spot atop their rotation on Opening Day.