He is hitting .476 (10-for-21) with a double, three home runs and five RBIs in five games since rejoining the team.
"Nothing's really surprising about K.K.," Rays manager Kevin Cash said. "We've got to see him play now for three years and know he's a special player. He's like anybody else, when he's seeing the ball well, a lot of good things can come."
He got the Rays' offense started Wednesday with a two-run homer in the third off Marcus Stroman ("Stro Show"). He added a solo home run in the fifth, giving him the second multi-home run game of his career (also Sept. 8, 2016, at Yankee Stadium).
"I'm just trying to hit the ball hard, trying not to miss pitches," Kiermaier said. "I've been doing a good job of it lately. ... I'm happy with how I'm feeling at the plate, but it's overshadowed by a loss."
Kiermaier did plenty of damage with his bat, but when he walked to open the seventh he used his speed to get the job done, too.
First, he stole his 11th base of the season to move to second, then advanced to third on catcher Raffy Lopez's throwing error. After Lucas Duda walked, he scored on Evan Longoria's infield single, tying the game at 6 and effectively negating the Blue Jays' early 5-0 lead.
Tying the game felt like a swing of momentum in the Rays' direction. Kevin Pillar ("Pill") changed that with the ninth home run of Wednesday night's game, which proved to be the deciding run.
"A couple of rough innings to start off, but our offense did a great job of battling back," Kiermaier said.
As good as Kiermaier has been since he's been back, he's disappointed about the big picture.
"At the end of the day, I'm trying to do my part to help the team offensively, defensively and on the bases, he said, "but the most important thing to me and the team right now is winning and we let a tough one get away from us tonight."
Bill Chastain has covered the Rays for MLB.com since 2004.