With Encarnacion one home run shy of matching the record for most in May, the Blue Jays attempt to rebound from their first defeat in 10 games Friday night against the Royals.
Encarnacion has 16 homers this month, a number surpassed only by Barry Bonds' 17 in May 2001.
The first baseman, who has two games left to match the mark, hit a pair of two-run shots in Toronto's 8-6 loss to Kansas City on Thursday.
Encarnacion now holds the Blue Jays record for most home runs in any month after his fifth multihomer performance of May, tying a major league record shared by Albert Belle (September 1995) and Harmon Killebrew (May 1959).
"I don't know where it goes down in history, but it's pretty historic in my mind," manager John Gibbons said.
The Blue Jays (32-23), however, are looking to regain their winning touch after their nine-game run ended Thursday. Giving the ball to J.A. Happ (4-1, 3.34 ERA) could help.
The left-hander has won three straight starts with 2.50 ERA and is coming off his best performance of that stretch. He yielded four hits with seven strikeouts in seven scoreless innings of Sunday's 3-1 win over Oakland.
"He's filling up the strike zone," Gibbons said. "He's locked in right now."
Happ hasn't quite done that against the Royals, going 2-1 with a 5.40 ERA in three starts. He struggled in the only meeting in Toronto on Sept. 1, giving up all of the Royals' runs in the first three innings before leaving after the fourth in a 5-0 defeat.
Kansas City (25-28) halted a four-game slide with 14 hits Thursday after shuffling responsibilities amongst its coaches, making Dale Sveum the hitting coach and Mike Jirschele third-base coach. Pedro Grifol, who took over as hitting coach last season, was reassigned as a catching instructor.
"They sure looked a lot better," manager Ned Yost said. "That's kind of what you hope for. You get a different voice and it kind of snaps everybody back to reality a little bit."
Omar Infante had two hits and three RBIs on Thursday after going 2 for 10 in his first three games since returning from a back injury.
Jason Vargas (4-2, 3.55) has posted a 1.62 ERA in five road starts, though the left-hander has gone just 1-0 in those games as the bullpen has surrendered nine runs - six earned - in 9 1-3 total innings over that span.
The relievers let Vargas down again Sunday in a 4-3 road defeat to the Los Angeles Angels. He threw 6 1-3 innings of one-run ball and left with a two-run lead, but Kevin Herrera and Tim Collins proceeded to waste the effort by surrendering three runs.
Vargas hasn't been very effective at Toronto, losing both of his starts there while giving up seven runs and eight walks in nine innings.
He allowed five runs and 10 hits in 6 1-3 innings while not getting a decision in a 10-7 home win over the Blue Jays on April 29. However, he held Encarnacion hitless in three at-bats.
Encarnacion has 33 RBIs this month, and he's 8 for 19 with five homers while driving in nine runs in five games.
"Encarnacion is probably the hottest hitter on the planet right now," Yost said.