LOS ANGELES -- The Twins designated Craig Breslow for assignment on Monday in a move that could conceivably end the career of the left-handed reliever. Additionally, the Twins outrighted Rule 5 reliever Justin Haley and sent him back to Boston. The vacated 40-man roster spots will be taken by left-hander Jaime Garcia and catcher Anthony Recker, both of whom were acquired in a trade with the Braves on Monday.
Breslow, 36, posted a 5.23 ERA in 30 appearances this season, his 12th in the Majors. He allowed 12 earned runs over his past 10 innings.
"Craig was a hard one, given the character of the man and what he brought here," Twins manager Paul Molitor said. "Part of the reason we're still at least somewhat relevant for now here as we head into late July is I think the clubhouse culture has been upgraded tremendously, and he was a big part of that."
Minnesota recalled right-hander Alan Busenitz in a corresponding move. Busenitz, a rookie, allowed two earned runs in six appearances over a two-week stint for the Twins in June. He owned a 1.78 ERA at Triple-A Rochester with 39 strikeouts in 35 1/3 innings. He'll be used in middle relief.
"He's an interesting guy," Molitor said. "He can run it up there. We asked him when he went back to work on that breaking ball. We want him to use it to get back into counts or even as a chase pitch. But we like his arm and his tenacity. It's good to have him back."

Haley, meanwhile, had been out since May 28 with right shoulder soreness and his rehab assignment was due to expire on Tuesday. Haley, 26, posted a 6.00 ERA with 14 strikeouts and six walks in 10 appearances with the Twins. He also had a 3.63 ERA in five appearances, including four starts on his rehab assignment with Triple-A Rochester.
"It was a real tough decision," Molitor said. "We had talked about what we were going to do with Justin with his rehab window closing. It came down the roster issues we're experiencing and creating space. We were only a month away from expanded rosters, but we felt like it was something we had to do."
Drafted in the 26th round out of Yale in 2002, Breslow turned himself into one of baseball's best middle relievers. He made 569 appearances for seven teams, including two stints each with Minnesota and Boston.
Breslow won a World Series with the Red Sox in 2013, and he owns a career 3.45 ERA. Though he profiled as a left-handed specialist, Breslow held righties and lefties to nearly identical batting averages against over his career.
But Breslow had struggled with diminished velocity over the past few seasons, pitching to a 4.98 ERA over 150 appearances since 2014. He tried changing his arm angle this year in an attempt to revive his career, but struggled with his command.
Breslow, who majored in molecular biophysics and biochemistry, is considered one of the smartest players in baseball by many of his peers.