OAKLAND -- The first order of business in improving the A’s bullpen began with bringing back one of the club’s most reliable arms.

Veteran reliever Yusmeiro Petit had his $5.5 million club option exercised by the A’s on Thursday afternoon. The 34-year-old right-hander has shown no signs of slowing down as he’ll enter his 13th big league season coming off a stellar 2019 campaign during which he posted a 2.71 ERA over 83 innings. Petit's career-high 80 appearances also led all American League relievers.

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Petit’s return was seen as a no-brainer by both sides at the end of the season. He expressed interest in returning to the club, while Oakland manager Bob Melvin made it clear how much value the righty brings to the team, not only as a late-inning weapon who can go multiple frames, but also as a resource for the younger arms.

“I feel good here. I want to be here,” Petit said after the A’s loss to the Rays in the AL Wild Card Game. “It’s been a special last two years, and I think next year has a chance to be even more special.”

Petit was one of the few bright spots in a bullpen that struggled to hold leads as it led the Majors with 30 blown saves. He recorded 71 strikeouts while issuing just 10 walks, and his 2.2 WAR was the highest of his career.

While Petit’s club option was picked up, left-hander Jake Diekman had his option declined, making him a free agent. Diekman was acquired in a trade with the Royals on July 27 in an effort to bolster the bullpen, and the results were mixed. He looked dominant at times with a high-velocity fastball, but his command was an issue. In 28 appearances with Oakland, Diekman went 1-1 with a 4.43 ERA, striking out 21 and walking 16 over 20 1/3 innings.