Happ allowed just one hit and utilized an effective changeup to throw 5 1/3 scoreless innings while J.P. Arencibia and Colby Rasmus homered in the Blue Jays' 5-0 victory over the Red Sox at Rogers Centre.
"I think that's going to be a big pitch for me," Happ said. "I had a couple of good ones today, trying to keep them off-balance. I think it makes the fastball that much better.
"I used to use it quite a bit and I'm trying to get back to the point to find that comfort zone with it. It can be a feel pitch, so when it's not there it makes it tough, but it was working for me pretty good today."
When Happ first broke into the Major Leagues, he was throwing the changeup on a regular basis. He used it 19 percent of the time in 2008, and by '10 the frequency increased to 22 percent, according to Fangraphs.
The numbers of changeups drastically dropped the past two seasons, though, as Happ used it just 14 percent of the time in 2011 and only nine percent last year. The plan is for that to change this season, because it's a pitch that has the ability to make his low-90s fastball more effective.
The recent problem Happ had with the changeup is that he lost the feel for the pitch. The southpaw worked on it a lot during Spring Training, and while it's just one start, the early results are at least encouraging.
"You can classify him as a power lefty. A lot of those guys don't use it that much, but your better left-handed pitchers have that changeup," manager John Gibbons said.
"It'll be big for him. He's got that fastball that he can throw by you up in the zone. That's kind of his trademark. If he gets that changeup going, that makes his fastball even better, and that'll complement his breaking ball as well."
Happ opened the game by surrendering a leadoff double to Jacoby Ellsbury, but from there, Happ was relatively flawless. He didn't allow another hit and had just two of his baserunners reach scoring position on the afternoon.
The only real problem with Happ's outing is that he frequently found himself in deep counts. That was one of the main reasons he wasn't able to complete the sixth inning. After 99 pitches and making his first start since a March 27 Grapefruit League outing, Happ was beginning to fatigue.
Happ's future goal will to be pitch deeper into games -- something that has been an issue for him in the past -- but for now the Blue Jays will be more than happy with what they got from their final man in the rotation.
"Happ did a good job of staying out of the middle of the plate," Red Sox manager John Farrell said of his former pitcher who struck out six and walked three. "Fastball, changeup, he's got deception. Swing and miss to his fastball. We saw it a number of times today.
"You couldn't sit on any one pitch in a given area. We had the one opportunity where he walked the guys in the one inning, but he made some pitches to get out of any jams."
Arencibia provided the early offense in the fourth inning when he sent a 2-1 pitch from right-hander John Lackey over the wall in straightaway center field. The two-run shot was Arencibia's third of the season, as he continues to build off a strong Spring Training.
Lackey, who was making his first start since having Tommy John surgery in October 2011, had been effective on the mound for Boston, but he unfortunately had to depart the fifth because of a strained right biceps.
Reliever Alfredo Aceves ended the fifth cleanly, but in the sixth, he surrendered a deep home run to center fielder Colby Rasmus. The ball carried so far that it hit the facing above what used to be called Windows Restaurant in right-center field and traveled an estimated 448 feet.
The Blue Jays have had some difficulty manufacturing runs early this season, but so far, the home runs have been there. Rasmus' shot was his second of the year and 11th overall by the ballclub.
"I've hit a few pretty far, but I hit that one pretty good," said Rasmus, who has four RBIs in five games. "That one was pretty close to the top.
"I've been feeling all right [at the plate]. There's good pitchers out there getting paid good money to get me out. They've been making adjustments on me and I just have to keep making adjustments on them. It's part of the game, but overall, I've felt good. I feel like I'm moving in the right direction."
So are the Blue Jays, who have won two of their past three games after starting the season 0-2.