The Indians said Kluber does not need surgery -- for now.
Kluber sustained what was believed to be a non-displaced fracture of his ulna bone when he was hit by a 102 mph line drive off the bat of Miami's Brian Anderson on Wednesday. He underwent further tests Thursday at the Cleveland Clinic, and the results confirmed the diagnosis.
Manager Terry Francona said Kluber's arm will be immobilized for the next week -- the Indians will keep him out of the dugout to prevent his arm from being bumped -- and the 33-year-old will be X-rayed once a week. The cast will be removed in three weeks, when doctors will decide what's next.
Francona said the club avoided guessing at a recovery time.
"No. 1, it doesn't help," Francona said. "And two, it's not really fair to the player. That's exactly how they [doctors] laid it out. Bones need to heal. They have an approximation because they're really good at what they do, but that's why we're going to have it looked at approximately once a week just to see the healing."
Kluber was not available for comment, but Francona said the right-hander is handling the injury with typical resolve.
"He goes, 'This is the hand I was dealt. Got to play it,'" Francona said. "My guess is -- it's not a guess -- when they give him the go-ahead to do something, he'll do it like crazy. Whether it's lower-half or whatever, he'll get after it like he always does."
The loss of Kluber is a major blow to the Indians, who trail Minnesota in the American League Central by three games and haven't been hitting well, batting an AL-low .215 with just 111 runs this season. Cleveland is missing two starters from one of baseball's best rotations, as Mike Clevinger remains out with a strained back muscle.
For that reason and to keep his players focused, Francona called a meeting before the series opener against Seattle to address the recent misfortune.
"Just to remind guys who we are, what we stand for," Francona said. "One of the first things I tell them at spring training is how we handle adversity kind of defines how your season goes. I don't see where teams aren't going to come in and feel sorry for us. This can be our time to shine, or we can feel sorry for ourselves and lose. We want to make sure we scratch and claw and do everything we can."
Kluber, a two-time Cy Young Award winner, was not pitching up to his standards early this season, but the right-hander is still the club's ace and a leader.
"It's never good news, especially when it's the ace of your staff that goes down," said Clevinger, who looked good while throwing from 90 feet before batting practice but isn't close to pitching in a game. "It is tough, but it's the next-man-up mentality. We've been having that same problem since 2016. This isn't really new with the Cleveland Indians, this injury bug. We've got the pieces to keep rolling."
In the meantime, Francona will juggle his rotation. Cody Anderson, who has missed most of the past two seasons following Tommy John surgery, will make his first start on Sunday against the Mariners. Trevor Bauer is being pushed back one day to face the Chicago White Sox, with Jefry Rodriguez scheduled to pitch Tuesday.
Francona said it's vital for the Indians to not look too far ahead. He has always professed a one-day-at-a-time approach, and it's imperative to follow that now.
"Our job is to take everything that happens and turn it, from what potentially could be a negative, into a positive. That's what you try to do every day," he said. "Our job is to believe we can win tonight's game by one run. It's kind of what we have to do. We just need to beat the Mariners tonight by one. Keep it in smaller segments, and it sort of makes it a little easier."
The Associated Press contributed to this report.