© 2014 MLB Advanced Media, L.P. All rights reserved.

6/18/2014 8:38 P.M. ET

Brantley diagnosed with mild concussion

CLEVELAND -- Indians left fielder Michael Brantley has been diagnosed with a mild concussion. He was out of Wednesday's lineup before the game was postponed due to weather.

The team had sent Brantley to undergo further testing on Tuesday, and ultimately it was determined that he would need to deal with the league's concussion protocols before being medically cleared to return. However, because the concussion is less severe than what catcher Carlos Santana suffered in May, Brantley could avoid the 7-day concussion disabled list and be back on the field by Saturday.

"The way it was explained to me, it's the type of concussion that should go away faster," Cleveland skipper Terry Francona said. "And I think we're actually seeing that."

Brantley played catch, hit off a tee and managed to get a workout in before Wednesday's game was postponed, mentioning that all his feedback from the team's medical staff has been positive to this point.

"I don't want to put a deadline on anything," Brantley said of his potential Saturday return. "But my goal is to get back out there with my team as fast as possible. That involves listening to the medical staff and making sure I'm ready to go 100 percent."

The Indians made Brantley a late scratch from Tuesday's game after he complained of concussion-like symptoms during his pregame routine. He was removed from Monday night's tilt with the Angels after he collided with shortstop John McDonald at second base while attempting to break up a double play. The decision had initially been called precautionary.

Brantley has hit .323 with a .391 on-base percentage this season, and he leads the club in home runs (11), RBIs (46) and runs scored (49). He was named the American League Player of the Week on Monday and has garnered the seventh-most fan votes for the All-Star Game among AL outfielders.

"If he's playing Saturday, he's fine," Francona said. "Because that's the last thing we want to do is run someone out there that shouldn't be. But because of the importance to the lineup and who he is, we'd like to try to have him back as soon as we can."

McAllister returns to Tribe's rotation

CLEVELAND -- Right-hander Zach McAllister is back in the Indians' rotation, and Josh Outman is out of the bullpen as a result.

On Wednesday, the team activated McAllister from the 15-day disabled list. Outman, a lefty reliever who has a 3.28 ERA in 31 appearances this season, was designated for assignment to clear a spot on the roster. The original plan was for McAllister to start on Thursday, but due to Wednesday's game being postponed due to inclement weather, Justin Masterson will now start on Thursday. The Indians haven't announced the rotation plan after that.

Normally, a starting pitcher is activated on the day of his start. But with Outman already unavailable to pitch on Wednesday and the bullpen in need of safeguarding, the Tribe opted to bring in McAllister a day early.

"If something fluky happens [on Wednesday], we protect ourselves without making four moves," Indians manager Terry Francona said before Wednesday's game was postponed.

The Indians can either trade or release Outman within the next 10 days. If he clears waivers, he can also accept an outright reassignment to a Minor League team.

Despite surrendering two runs in 1 1/3 innings on Tuesday night, Outman -- a lefty specialist -- has held left-handed hitters to a .180 average and a .673 OPS this season. However, right-handers are batting .295 against him this year and he's had command issues, which left the team willing to risk losing him to a waiver claim.

Rookie southpaw Kyle Crockett's meteoric rise to the Major Leagues also influenced the decision, as he had essentially taken over Outman's old responsibilities.

"When Crockett came to [Cleveland], it kind of changed Josh's role," Francona said. "You're looking for a little bit maybe in length; I'm not sure that role really fit him. We feel that Crockett can throw strikes, that he's going to do nothing but probably get better."

Crockett has pitched 2 2/3 scoreless innings since being recalled from Triple-A Columbus on Friday.

McAllister, who struggled to a 5.89 ERA in 10 starts with the Tribe, returns to the club after going on the disabled list on May 22 with a sore back. He made his third rehab start on Saturday, scattering five hits over four scoreless innings while fanning two.

"I felt good. I was happy with it," McAllister said on Monday. "[I threw] 65 pitches, was able to throw about 70 percent strikes."

Quote to note

"Sometimes you don't feel it for whatever reason. It's a challenge. The good side for us is how much we believe in Masty. We all get challenged, but he'll tackle it and he'll figure out a way to be Masty. That saves us all some sleep because we believe in Masty so much."
-- Francona on Justin Masterson, who exited after two innings on Friday for the second-shortest outing of his career.

Smoke signals

• Double-A Akron outfielder Tyler Naquin saw his 17-game hitting streak come to an end with an 0-for-4 performance on Tuesday. He hit .431 with seven extra-base hits, eight RBIs and 16 runs scored during that span.

Alec Shirkey is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.