Mercado went 5 for 5 and drove in two runs as the Indians won their sixth straight game, beating the Kansas City Royals 10-5 on Friday night.
Mercado had an RBI double in the third inning and a run-scoring single in the sixth. He also scored twice, but preferred to focus on the fact the Indians have won 12 of 14 and trail Minnesota by three games in the AL Central.
"It feels good, but it feels even better to be playing the way we are," Mercado said.
Mercado lined a single to center off Wily Peralta in the eighth with Francisco Lindor on second, but said getting a fifth hit wasn't his priority.
"It was a 7-5 game and my job there was to move him over," he said. "At the end you don't really think about it. You have to stay within your game and understand the game and do your job."
Mercado battled a slump going into the All-Star break, but is batting .423 (11 for 26) with three home runs and eight RBIs over the last eight games. He was called up from Triple-A Columbus on May 14 and became the 12th Indians rookie since 1913 to have at least five hits in a game.
"Everybody's going to go through a tough stretch, but you know a first-year player is," manager Terry Francona said. "And to see him not wilt, to see him come back with a vengeance, that's pretty exciting."
Shane Bieber (9-3), making his second start since being named MVP of the All-Star Game held at Progressive Field, allowed five runs in 5 2/3 innings.
Bieber took a 6-2 lead into the sixth, but three straight singles with two outs loaded the bases. Whit Merrifield's three-run triple off Nick Goody cut the lead to one.
Cleveland scored four times in the third to erase a 2-1 deficit. Tyler Naquin hit a two-run homer, a towering drive down the right field line that hit close to the top of the foul pole.
José Ramirez drove in two runs and extended his hitting streak to 11 games with an RBI single in the eighth.
Mike Montgomery (1-3) got the loss in his debut for Kansas City after being acquired from the Chicago Cubs for catcher Martin Maldonado on July 15. The left-hander allowed five runs in two innings and was pulled after the first four hitters in the third reached base.
Montgomery went 1-2 in 20 relief appearances for the Cubs, but the Royals will use him as a starter.
Bieber's bases-loaded balk in the first inning scored a run for Kansas City. Jordan Luplow tied the game in the first with an RBI grounder.
Kansas City, which was 6-1 since the break, went ahead in the third on Hunter Dozier's RBI double. Alex Gordon tagged up from third on Humberto Arteaga's fly ball to right and was called safe after avoiding the tag of catcher Roberto Pérez.
Pérez lunged at Gordon, who jumped around the catcher and touched the plate with his hand as he was being tagged. The Indians challenged and the call was overturned.
Royals manager Ned Yost didn't believe there was conclusive evidence to change the call.
"It very much surprised me," he said. "We'll look at it and send the video in again."
Royals: SS Adalberto Mondesi has begun rehabilitating his partially dislocated left shoulder. He was injured diving for a foul ball against the White Sox on Tuesday and placed on the 10-day injured list.
Indians: RHP Corey Kluber (broken arm) played catch and did long toss for about 20 minutes. He's scheduled to throw off the mound Sunday for the second time since being struck by a line drive May 1.
Montgomery recorded the final out of the 2016 World Series for the Chicago Cubs against the Indians at Progressive Field.
"I thought about it when I walked out to the mound," he said. "You definitely never forget those memories, but you put them in the back of your mind."
Montgomery made a relief appearance for the Cubs in Cleveland last season.
Royals: RHP Jakob Junis (5-8, 5.08 ERA) struck out a career-high 10 over seven innings Monday in a 5-2 win over the White Sox.
Indians: RHP Adam Plutko (3-1, 5.40 ERA) is seeking his first victory over the Royals. He is 0-1 with a 5.06 ERA in four career appearances against KC.
More AP MLB: https://apnews.com/MLB and https://twitter.com/AP_Sports
Copyright 2019 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.