The left-hander came through with six solid innings and, with two home runs and three RBI from Edwin Encarnacion, the Blue Jays defeated the Cleveland Indians 4-2 on Thursday.
Happ (2-1) allowed six hits, two walks and one run, on a homer by David Murphy in the fifth inning, in his third start of the season. The left-handed pitcher believes preparation with Kratz was the key to his success.
"We went over some stuff before the game about how we wanted to attack them a little bit more deliberately," Happ said. "And for the most part we were able to do that."
Blue Jays manager John Gibbons, who won his 400th game with Toronto, liked how the team's starting battery operated.
"(Happ) stepped up," said Gibbons. "I thought Kratz did a nice job with him, working that fastball on the inside part of the plate. That was big for him, it really was. And big for us."
Happ's control impressed the Indians lineup as well.
"His fastball was really getting on guys," Cleveland left-fielder Ryan Raburn said. "I know it's 92-93 but out of his hand, it just seemed a lot harder. And he spotted his pitches. He didn't miss over the plate a whole lot from what I saw."
Encarnacion, who has eight homers on the season, also had a double and lined out to third in his other at-bat.
Juan Francisco hit his seventh homer of the season for the Blue Jays (21-21) who won the rubber match of a three-game series with the Indians (19-22) to complete a 5-4 home stand.
If Happ is battling to prove to some people that he belongs in the rotation, he preferred not to discuss it in detail.
"I don't want to get into that," Happ said. "I think you're always doing that to somebody. That person may change or those people may change."
Encarnacion has been the designated hitter for the past two games with Adam Lind playing first base. The change was made just before Wednesday's game because Encarnacion had spasms in his upper back.
"It felt a lot better today, so I'm ready to go," Encarnacion said. "I felt a lot better at the plate. The last couple of games I've been getting hits. I've been great at the plate the last couple of weekend, and it makes me happy and very proud because when I play like that I know I can help the team win."
"He's one of the top sluggers in the game," Gibbons said. "Got off to a slow start, then he kicked it in. You look where he's at now, too, he's been barrelling a lot of balls all year, especially the last month, and a number of times he got nothing to show for it. So numbers could be even better now with little breaks here or there, a little luck.
"But he's key to this team, of course with him and (Jose) Bautista back to back. That's big. Of course, Lindy and now with Francisco. Those two (Encarnacion and Bautista), we know what to expect, they're a given. But I like the way our lineup looks now. It's that much stronger, top to bottom."
Cleveland dropped to 4-10 when facing a left-handed starter, 0-8 on the road, this season. Happ opened the season on the disabled list with a sore back and began pitching from the bullpen on his return.
Casey Janssen, who also started the season on the disabled list, pitched the ninth for his second save of the season.
Cleveland right-hander Danny Salazar (1-4) needed 98 pitches to work through four innings and was replaced by right-hander C.C. Lee to start the fifth with the Blue Jays leading 2-1.
Salazar allowed five hits, including second-inning homers by Encarnacion and Francisco, two walks and two runs. He also hit a batter.
"I just didn't have a good feeling for the ball today to command my fastball, and my change-up wasn't there," Salazar said.
He felt that he made a good pitch on Francisco's homer.
"I was just behind in the count," he said. "They're going to be ready to hit everything there."
Lee faced two batters. Bautista led off the fifth with a single and Encarnacion lofted a drive to left on a 3-2 fastball. It was the second time he has hit two homers in a game this season and it was the 13th multi-homer game of his career.
Left-hander Brett Cecil pitched the seventh for Toronto and right-hander Steve Delabar took over in the eighth and was greeted by Raburn's double. Carlos Santana walked. But Asdrubal Cabrera lined out to right and pinch hitter Lonnie Chisenhall lined out to centre. Yan Gomes singled up the middle to cut the lead to two runs and bring in left-hander Aaron Loup. He struck out Murphy, who had five hits and five RBI in Cleveland's 15-4 win on Wednesday.
NOTES: Right-hander Dustin McGowan, who is 2-2 with a 5.08 earned-run average in eight starts, has been removed from the starting rotation and will pitch from the bullpen. Right-handers Marcus Stroman and Todd Redmond are candidates to start in his place next Tuesday in Boston. Right-hander Liam Hendriks who is 5-0 with a 1.51 ERA at triple-A Buffalo is another possibility. … Centre-fielder Colby Rasmus (hamstring) was placed on the 15-day disabled list on Thursday and outfielder Anthony Gose was recalled from Buffalo. …The Indians put outfielder Nyjer Morgan (right knee sprain) on the DL and called up infielder Jesus Aguilar from triple-A Columbus. … The Blue Jays travel to Arlington, Tex., to play the Rangers in a three-game series that opens Friday with Drew Hutchison (1-3, 4.37 ERA) starting against Yu Darvish (3-1, 2.33 ERA).