Jon Lester reached a career high with 12 strikeouts Sunday in Toronto.

AP photo / The Canadian Press, Darren Calabrese

TORONTO –– After each disappointing start this year, Jon Lester has maintained that he is only one step away from putting it all together. Little things were his undoing, he insisted, and once he can eliminate the singular errors, he will be just fine.

Sunday, he backed up his words, pitching an excellent six-inning, 12-strikeout three-hitter, and carrying his team to a victory on the road.

It was a career-high in strikeouts for Lester, and he did it by mixing up pitches, incorporating his newly adopted changeup more than ever before.

"I used it a lot today, and I was able to get some swing and misses. I think more than anything, it just planted a seed in their mind, that I was throwing it, and I was throwing it in different counts, ahead and behind. Yes, I think today, it did have an effect, especially with this lineup," Lester said.

The last time he faced Toronto, Lester barely used his change, which he honed during spring training.

"He probably threw 20-some changeups, so he was a totally different guy than we’ve seen before," catcher Jason Varitek said.

Lester won 16 games last year, with a 3.21 E.R.A. The team responded by inking him to a five-year, $30-million deal in the offseason with an option for a sixth year.

But from the start, Lester has had a vexing year. He has pitched well, but in most outings, one bad inning undid five or six good ones. His E.R.A. is now down to 5.65, and despite a disappointing outing against Minnesota last week, when a Justin Morneau home run changed the game, he feels like he is pitching well.

"I think I’m going in the right direction. Obviously the result of one start wasn’t where I wanted it to be, but if you take the 98 or 99 pitches I threw that game, there’s only one pitch that hurt me. I’ll take those odds every start."

Sunday, in the first inning, Lester appeared to be headed in that direction, but with two men on, he got out of it with a strikeout, having only given up one run.

"It was big. Obviously, I was frustrated in the first inning, but I was able to limit the damage to one run. That’s been a focus of mine this year, and obviously the past couple starts," he said.

Lester is striking out more than a batter an inning, which is well ahead of the pace he’s set in his early career. He insisted the strikeouts are a bonus, not a focus, and his manager concurred. Lester is the kind of versatile pitcher who can strike out a dozen hitters one outing, pitch to contact the next, and have success.

"With his stuff, he will have strikeouts. But there’s going to be games where his two-seamer is working, and they’re putting it in play, and he’s not going to have a lot of strikeouts, and we’re thrilled," Francona said.

For his teammates, it was simply a fun show to watch.

"He was awesome," second baseman Dustin Pedroia said. "That was some of the best stuff in baseball that he threw out there today."

dbarbari@projo.com