ST. PETERSBURG -- The Rays spent most of this past season without right-hander Nick Anderson, their most effective reliever from the time they acquired him in 2019 until the end of the '20 season. Now, it appears Anderson will be sidelined for most of next year as well.

Anderson underwent right elbow surgery on Wednesday, the Rays announced Thursday, and isn’t expected to return to game action until after the 2022 All-Star break. Anderson will be sidelined from throwing for three to four months, according to the team. The operation, performed by Dr. Keith Meister in Dallas, repaired Anderson’s ulnar collateral ligament with an internal brace procedure.

The procedure is considered an alternative to Tommy John surgery, designed to support the ligament and significantly cut down on the recovery timeline. Seth Maness and former Ray Rich Hill are the most notable pitchers to undergo the operation, also known as a “primary repair.”

Anderson was arguably the best high-leverage reliever in baseball from the time he was traded from the Marlins to the Rays on July 31, 2019, until the early rounds of the 2020 playoffs. The right-hander put together a 2.11 ERA with Tampa Bay in '19 and a 0.55 ERA over 19 outings last year, striking out 67 of the 136 batters he faced during that stretch.

He began to falter in the 2020 postseason, however, allowing a run in each of his final seven outings -- including Game 6 of the World Series -- while striking out only five of the 45 batters he faced in those appearances. Anderson reported to Spring Training this year with diminished velocity, and eventually learned he had a partially torn ligament in his throwing elbow.

Anderson did not pitch in a game until July 23, when he began a Minor League rehab assignment with the Rookie-level Florida Complex League Rays. He was idled for a few weeks for COVID-19-related reasons, then joined Triple-A Durham from Aug. 12-Sept. 8. Finally, Anderson made his season debut in the Majors in Toronto on Sept. 13. But he returned with noticeably reduced fastball velocity, clocking in at 93 mph on average compared to 95.2 mph in 2020 and 96 mph in ’19.

Anderson gave up three runs on four hits in six innings for the Rays in September, striking out only one of the 24 batters he faced, before going on the 10-day injured list on Sept. 27 due to a low back strain. Anderson was deemed healthy when the Rays’ postseason run began, but he was left off their American League Division Series roster.

The 31-year-old reliever is eligible for salary arbitration for the first time this offseason. The Rays have plenty of bullpen depth to make up for the loss of Anderson, as they displayed throughout this year, but they could pursue another veteran arm this offseason to further strengthen that group.

While Collin McHugh and David Robertson will depart as free agents, Tampa Bay still has high-leverage arms set to return in Andrew Kittredge, Pete Fairbanks, J.P. Feyereisen, JT Chargois and Matt Wisler. Ryan Thompson and Jeffrey Springs, who worked in high-leverage situations early on this past season, are also expected to return to the bullpen after finishing the season on the 60-day IL.