"He's going to be down for I'd say a minimum of 10 days," Indians manager Terry Francona said. "Rather than put too much of a timetable on it, when he's ready, we'll pitch him. That's kind of where we are there."
With Kluber scratched from Friday's scheduled start in Detroit, right-hander Josh Tomlin moved up a slot to start the opener of the three-game set against the Tigers and tossed a four-hitter in the Indians' 8-1 win. Righty Danny Salazar is now slated to start against Detroit on Saturday and righty Cody Anderson will get the nod for Sunday.
Righty Trevor Bauer started on Wednesday in Toronto, putting him on pace to start on Monday in the opener of a three-game road series against the White Sox.
Right-hander Carlos Carrasco is on the 15-day disabled list due to a right shoulder issue but could be activated for a start on Tuesday in Chicago, barring any setbacks.
The 29-year-old Kluber has not started since Saturday in Cleveland, but the righty tweaked his hamstring initially during a mound session on the Indians' recent trip to Toronto. According to Francona, the issue worsened later when Kluber tried to run through some conditioning drills
"He went and conditioned, and probably exacerbated it a little bit," Francona said. "I still think he thought he was going to pitch. The more the trainers looked at him, we had the day off [on Thursday], [so we] thought, 'OK, let's get him back to Cleveland, get him looked at.'"
In recent weeks, pitchers have taken to kicking a soccer ball around and playing catch with a football during pregame drills. Francona said Kluber, who often takes part in those fun workout sessions, did not injure himself in a non-baseball activity.
"We want the guys to enjoy [themselves]," Francona said. "But, we don't ever want something to happen that shouldn't. So, [Indians strength and conditioning coach Joe Kessler] was always there when the football''s there, so no. He felt it first when he was in the bullpen."
In 28 starts this season for the Tribe, who headed into Friday's action with a 64-68 record and a six-game deficit in the race for the AL's second Wild Card, Kluber has gone 8-13 with a 3.41 ERA, 219 strikeouts and 38 walks in 200 1/3 innings. He also ranked fourth among AL pitchers with a 5.2 WAR (per Frangraphs.com), entering Friday.
Kluber also has a 2.63 ERA with 43 strikeouts, six walks and two complete games in his past five outings (37 2/3 innings), and he has posted a 2.95 ERA over his past 21 starts, dating back to his 18-strikeout performance on May 13 against the Cardinals.