CHICAGO -- An ace’s job in a starting rotation is to provide a sense of certainty for his team that more times than not, he is going to give his club a chance to win. Lucas Giolito is becoming that guy for the White Sox.

After an ugly defeat against Toronto on Friday night, Giolito continued to show in Saturday’s 4-1 victory over the Blue Jays that he can not only be the front man on the Sox staff, but be the stopper, as well.

The former No. 16 overall pick in the 2012 MLB Draft took another step forward in looking like an elite frontline starting pitcher, earning the win after a three-hour rain delay, and subsequent early finish, gifted him a five-inning complete game.

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“This was probably my first start this year where I’d consider it a grinder. I didn’t have my best stuff coming in. The first few innings [I was] throwing a lot of fastballs. Offspeed stuff wasn’t really working great, but I was able to make pitches, get out of situations, stay under control.”

“The maturation that he has shown and the ability to continue to repeat that delivery [has been impressive],” manager Rick Renteria said. “I think he feels like everything he’s doing right now will give him an opportunity to do what he wants on the mound.”

An ace can not only dominate a lineup, but get himself out of trouble when in a jam and minimize the damage even without his best stuff.

After a check swing single by Rowdy Tellez and a bloop double by Freddy Galvis put runners on second and third with one out in the second inning, Giolito was able to minimize the damage by getting the next two hitters out, allowing just one run to score.

The same happened in the fourth inning after giving up back-to-back walks to Tellez and Randal Grichuk with one out. Giolito got the next two hitters to pop out softly to end the inning; this time, he didn’t allow a run.

In the past, those innings would have snowballed on Giolito, but with his newfound confidence and adjustment in his mechanics, the 24-year-old can just attack.

“It’s all in the breath. If things are starting to go a bit haywire out there, I always go back to my breath,” Giolito said. “Step off the mound, take a big deep breath, forget about what happened and move on to the next pitch. I was happy with this one because in the beginning, I didn’t have my best stuff, but I was able to get through it and only give up one run.”

Even without what he called his best stuff, Giolito dominated when he needed to. With the rain coming down harder than it had all game, and knowing that getting the game to an official four and a half innings could mean victory, Giolito struck out the side in the fifth on 11 pitches to secure the win.

“I saw the rain coming down and said, ‘We gotta pick up the tempo a little bit.’ Luckily we were able to get through five and close it out there,” Giolito said about his final inning. “The raindrops were so big they were getting into my glove, on the ball, on my hands. So my approach there was just to attack the zone with a fast pace and hopefully get a nice 1-2-3 inning. Just going out there and emptying the tank in the fifth, which isn’t something I would normally do.”

“He doesn’t get flustered,” Renteria said of his young starter. “He’s very much under control of his emotions. A lot of those things he was working through last year.”

Giolito finished with just one run allowed on three hits. He struck out four Blue Jays hitters and walked two, earning his fifth win of the season.

He has now won three consecutive starts for the first time this season and the second time in his career. The previous instance came last season when he won three straight from Aug. 14-25.