BOSTON -- Red Sox president of baseball operations Dave Dombrowski was already looking to shore up his beleaguered bullpen when closer Craig Kimbrel was hurt shagging flyballs.
Suddenly, Dombrowski had another big hole to fill.
And he did.
The Red Sox acquired Arizona closer Brad Ziegler early Saturday, hours after learning Kimbrel would likely be sidelined for three-to-six weeks with an injured left knee. He was hurt during BP before Friday's win over Tampa Bay.
"I took a step for a groundball, heard a pop and didn't really think it was anything serious," Kimbrel said in the dugout about 75 minutes before Boston's game against Tampa Bay.
Kimbrel is expected to have surgery Monday for a medial meniscus tear.
Kimbrel had been selected for the All-Star Game on Tuesday. He was replaced on AL roster by Toronto right-hander Aaron Sanchez.
Red Sox manager John Farrell said Ziegler will share the closing duties with 41-year-old righty Koji Uehara, who got the save Friday despite allowing a solo homer to Evan Longoria.
"It's something we've been looking to do, try to add to our bullpen for an extended period," Dombrowski said. "We went back and forth numerous times, then finally agreed to the deal, really right toward the end of (our) game, during the game."
Kimbrel is 1/3 with a 3.55 ERA and 17 saves in 19 chances.
"I think that's the one thing Dave has proven over the course of his career, the proactive-ness or recognizing what our current needs are and being able to anticipate what we'll need when we go forward," Farrell said before Boston's game against the Rays.
Boston acquired Ziegler for two minor leaguers. The 36-year-old right-hander was 2/3 with a 2.82 ERA and 18 saves in 20 opportunities for the Diamondbacks.
Farrell said the team spoke with Ziegler about 1:30 a.m. after Arizona's game ended in San Francisco.
"We briefly discussed how things are going to shape up," Farrell said.
Uehara is 2/3 with a 4.96 ERA and three saves. He's struggled giving up eight homers in just 32 2/3 innings.
In 2012, then-Yankees closer Mariano Rivera tore a ligament in his right knee shagging balls in Kansas City.
Farrell said it was part of Kimbrel's cardiovascular work.
"Pregame conditioning went fine. There was a change of direction during shagging BP, which is routine, normal," he said. "This is anomaly. You can't put guys in bubbles."
Kimbrel said he won't reconsider his routine because it was a fluke, and only on a grounder.
"If I was shagging flyballs, maybe," he said. "I just took a step."
The Red Sox already had setup reliever Junichi Tazawa shut down for a few days with a sore shoulder. He's hasn't pitched since Sunday and Farrell said he's unavailable Saturday. They already lost setup man Carson Smith for the season after he underwent elbow reconstructive surgery in late May.
Ziegler was available because the Diamondbacks are far of the NL West chase, 17 back of the Giants. Arizona is 10 behind the New York Mets for the NL's second wild card.