CLEVELAND — Shane Bieber promised himself after undergoing Tommy John surgery last April that he would be honest about his rehabilitation process.

Even though the Cleveland Guardians ace is going through his first setback, Bieber is trying to remain optimistic.

Bieber is in the middle of a seven-day pause from throwing after experiencing soreness in his right elbow following his first rehab start on May 31 and a bullpen session on Tuesday.

The right-hander was scheduled to make his second rehab start with Double-A Akron on Friday before being shut down.

“My mind went back to a very close buddy of mine said a few weeks or a few months back when I was starting bullpens. He was like, ‘Just don’t freak out. If you get a setback, everybody gets at least one,'” Bieber said before Saturday’s game against the Houston Astros. “I was hoping to be that anomaly, but at the same time, maybe it’s just part of the process and I’m trying to listen to my elbow and my body and do what’s best for myself and the team in the long term.”

Bieber will be checked again the middle of next week before the team’s medical staff and specialist Dr. Keith Meister decide the next steps.

Bieber threw 21⅓ scoreless innings in an Arizona Complex League game on May 31, which was his 30th birthday. The 2020 American League Cy Young Award winner faced nine batters, allowed one hit and struck out five while throwing 42 pitches.

“I’m a little frustrated with the timing of it as I get out here to Cleveland and join the team, but unfortunately, these rehab processes aren’t exactly linear,” Bieber said. “I’ve had a fantastic progression up to this point. A small hiccup, but hopefully we’ll just keep it at just that.”

Bieber — who agreed to a one-year, $14 million contract last fall with a $16 million player option for 2026 — appeared to be on pace to return to the Guardians’ rotation in late June, but that could be delayed until after the All-Star break.

Cleveland (33-29) went into Saturday 7½ games behind Detroit in the AL Central, and a half-game out of a wild-card spot.

Guardians starters have the sixth-highest ERA in the American League (4.11).

NEW YORK — Boston Red Sox manager Alex Cora said Saturday that Alex Bregman felt good after starting a running program at Fenway Park but is still far from returning from a strained right quadriceps.

“The progression is going well,” Cora said before the Red Sox continued their series against the New York Yankees. “Let’s see how he feels tomorrow and then we’ll go from there, and obviously we’re still far away from him starting the baseball progression.”

Bregman has been out since May 23 with a significant strain, similar to his left quad strain that cost him 58 games for the Houston Astros in 2021.

Bregman started the running program Thursday. He will also have Sunday off before resuming running later next week.

Signed by the Red Sox as a free agent to a $120 million, three-year deal during the offseason, Bregman was hitting .299 and 11 homers and 35 RBI.

Marcelo Mayer, who hit his first career homer in Friday’s 9-6 loss, has made 10 starts at third base but was not in the lineup against left-hander Ryan Yarbrough and will likely be out of the lineup against southpaw Carlos Rodón on Sunday.

The Red Sox entered Saturday with nine losses in 13 games since Bregman was injured.

Cora also said Kutter Crawford is likely to throw a bullpen session at the end of next week as he tries to prepare for a minor league rehabilitation assignment. On Friday, Cora said Crawford was likely to throw a bullpen session this weekend.

Crawford hasn’t pitched in a game this year because of patellar tendinitis in his right knee. Cora had said Monday that the 29-year-old right-hander would start a rehab assignment this week, then said the following day that Crawford felt wrist pain. He said Friday that Crawford does not have any structural damage.

The Atlanta Braves designated nine-time All-Star reliever Craig Kimbrel for assignment Saturday.

Kimbrel, 37, made his season debut Friday night and allowed one hit in a scoreless seventh inning in Atlanta’s 5-4 10-inning loss at San Francisco. The right-hander had one walk and one strikeout and threw 14 pitches.

Kimbrel, who began his career in Atlanta in 2010, was called up from Triple-A Gwinnett prior to Friday’s game against the Giants. He signed a minor league deal with the Braves in March.

Kimbrel led the National League in saves in four straight seasons with the Braves from 2011 to ’14.

He ranks fifth all time with 440 saves and has a 2.59 ERA in 838 career games (no starts) over 16 seasons with eight teams.

Atlanta recalled left-hander Austin Cox, 28, from Triple-A Gwinnett in a corresponding transaction. He last pitched in the majors with the Kansas City Royals in 2023.

Also Saturday, the Braves claimed right-hander Jose Ruiz off waivers from the Philadelphia Phillies.

The 30-year-old was 1-0 with an 8.16 ERA in 14 1/3 innings for the Phillies this season.

Information from Field Level Media was used in this report.