OAKLAND – Back in 2016, J.B. Wendelken was just trying to establish himself as a consistent relief pitcher at any level of baseball.
The Savannah, Georgia native made his MLB debut with the A's that May, but struggled in eight appearances out of the bullpen. He allowed 14 earned runs in just 12 1/3 innings.
Wendelken wasn't much better in Triple-A, registering a 4.11 ERA and 1.61 WHIP in 46 innings for the Nashville Sounds. As it turned out, there was a reason for his struggles: He needed Tommy John surgery.
"It was very tough to stay positive because I knew something wasn't right," Wendelken recently told NBC Sports California. "Every day you go out there, it was something else – some ache, some pain. You knew something wasn't right but I did my best at the time. ... Deciding to do surgery was actually the best decision of my life."
Wendelken missed the entire 2017 season as he recovered from the procedure. He admitted the rehab process was difficult, and often lonely, but he had help staying positive.
"Family. My lovely wife. Everybody kept me on track," Wendelken said. " ... I had some bumpy times coming down that rehab road, but overall, just overcoming that situation, it's eye-opening that you still have family there behind you no matter how low your lows are."
When Wendelken returned to the mound in 2018, he was a brand-new pitcher. The young right-hander was throwing his fastball with precision in the mid-to-high 90s, while also locating his curveball and changeup with pinpoint accuracy.
"It was life-changing after surgery," he said. "I felt stronger and my confidence was up. ... It was a change for me with the feeling of how healthy I really was and that I could pitch here."
Even Wendelken couldn't have imagined how well he would pitch for the A's last season. In 16 2/3 innings, he allowed just one run, translating to a 0.54 ERA. He notched 14 strikeouts against five walks, and quickly became a trusted member of Oakland's bullpen.
"He was on the playoff roster for a reason," said A's manager Bob Melvin. "It all came together for him after his surgery to where the (velocity) was back and the command was back. His mechanics are as good as they've ever been."
"I definitely outdid my own expectations," Wendelken added. "My goal coming into last year was just to play for myself, try to enjoy the game again, and get back into it. I think I did that well with how I carried myself and went about my business."
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This season, Wendelken has picked up right where he left off, striking out 14 batters in 12 1/3 innings while walking just two. His 3.65 ERA is a little deceiving based on a stellar 0.81 WHIP and 2.65 FIP, which actually is better than last year.
"We expected him to be in this type of role based on what we saw last year," Melvin said. "A lot of guys have compared him to Lou Trivino's ascent. He's got a little bit to do before he gets to that level, but he's pitched himself into a role now where we're using him typically in plus games and, a lot of times, more than one inning."
Now 26 years old, Wendelken's patience and determination have paid off. He is firmly entrenched in the A's bullpen as one of the team's most reliable arms.
And he’s only just getting started.