The Cleveland left fielder needed stitches in his left forearm after being spiked Monday during the Indians' 14-10 win over the Oakland Athletics.
Brantley was hurt on a play that ended the third inning. A's third baseman Josh Donaldson gathered the ball near the pitcher's mound and raced Brantley to the bag, stepping on his arm as he applied the tag.
"I don't know how many stitches and you never like any injury, but in this case there was some relief on my part," Indians manager Terry Francona said.
"When he came off the field, his batting glove was hanging and I thought I saw his finger extended out at a weird angle. So, all in all, the news could have been worse. We'll evaluate him tomorrow," he said.
The 25-year-old Brantley hit .288 with 60 RBIs last season.
Brantley's injury dampened a win that made the Indians 5-0 in exhibition play under their new manager. Justin Masterson pitched two perfect innings in his first spring start.
"Today, it was two innings, nice and easy," Masterson said. "I was able to finish off pitches. I kept the ball on the ground and that is nice. It's good to have it in the zone and not get crushed. I had the sinker going and that's a good thing, especially in Arizona.
After scuffling to a 7-17 record in his first season and a half as a starter, Masterson seemed to come into his own in 2011. He posted a 12-10 record in 33 starts, walking only 65 in 216 innings, as the Indians stayed in the pennant race through the first half of the season.
But he fell off last season, dropping to 11-15 with a 4.93 ERA and a career-worst 88 walks in 34 starts.
"The thing for me is about relaxing and not trying to do too much," Masterson said. "If you can get outs throwing it at 90, 91 (mph), you don't always have to run it up there at 95, 97. You know you have something left in the tank."
"I think that was the case in about seven or eight bad starts last year. I was fine for the first two innings. Then I looked up at the gun and it said 91 or something. And I said, 'OK, now is time to do a little more.' But that is not always the case. Sometimes, less is better."
Against Oakland, Masterson retired the first five hitters on ground balls before striking out Hiroyuki Nakajima to end his outing.
Ubaldo Jimenez followed Masterson and allowed two hits, walked one and struck out two in his first two spring innings.
"Last year, even in spring training, I couldn't do anything right," said Jimenez, working with his fourth pitching coach in less than two full seasons since joining the Indians. "As a pitcher, you never want to give up runs at any time, but in spring training you work on things. I will work on keeping that shoulder right and not worry about other things."
All seven candidates for the Indians' rotation—Masterson, Jimenez, Brett Myers, Carlos Carrasco, Daisuke Matsuzaka, Trevor Bauer and Scott Kazmir—have pitched two innings in the team's first five games over four days. Only Myers and Carrasco surrendered any runs.
Matt Carson, who hit 14 homers for Triple-A Columbus last season, homered to straightaway center for the Indians in the sixth off Sonny Gray. Yan Gomes also homered.
Left-hander Andrew Werner, who at best may make the roster as a long reliever after being traded from San Diego to Oakland in November, started and allowed an unearned run on a walk in two hitless innings.
Shane Peterson hit a two-run homer in the sixth for Oakland against Matt Capps, who signed a minor league contract with the Indians after converting 14 of 15 save chances in an injury-filled 2012 season.
Michael Choice, Oakland's first-round pick in 2010, homered in the seventh.
"He's been swinging the bat awfully well and he's playing a good center field," A's manager Bob Melvin said.
NOTES: Indians 3B Ryan Raburn had an RBI single in the third inning, giving him six RBIs in his four games to go with three home runs and a .750 batting average (6 for 8). ... A's LHP Hideki Okajima, a non-roster invitee to camp, pitched the fourth. He walked the leadoff hitter and surrendered a one-out double before getting out of trouble with a pair of groundballs. Okajima was 0-2 with nine saves and a 0.94 ERA for his Japanese team last year. He was 17-8 with six saves and a 3.11 ERA in 261 appearances for the Boston Red Sox from 2007-11.