TORONTO -- For the first four innings on Friday night in Toronto, Padres starter Joey Lucchesi laid the groundwork for what had the potential to be a career outing.

It still was in some ways, with Lucchesi’s 11 strikeouts marking a new personal best in the Padres’ 6-3 win over the Blue Jays -- as Hunter Renfroe hit a tiebreaking three-run home run in the eighth inning to lift San Diego to its fourth straight victory. The 25-year-old Lucchesi has shown signs recently that he was due for a dominant outing, especially coming off an efficient start his last time out against the Pirates, where he needed just 77 pitches over seven innings.

• Box score

Not only was Lucchesi in full control through the first four hitless innings against the Blue Jays, but he did it without working deep into counts. Lucchesi has pitched seven full innings just twice in his career -- both this season -- and hit the 100-pitch plateau only three times.

One of the breakthrough moments for Lucchesi began two starts ago in Colorado, when he started forcing himself to “reset” between every pitch. By breaking his game up into individual pitches, Lucchesi feels much more confident in his growing mental game.

“I’ve kind of been psyching myself up before the games saying, ‘No one’s better,’ a kind of attack mindset,” Lucchesi said. “I’ve just been feeling really well with doing that before games and telling myself to reset every pitch. Every pitch is a fresh pitch.”

The fifth inning is where he finally hit some turbulence. Lucchesi walked Randal Grichuk, the first batter he allowed to reach base, and quickly surrendered a two-run home run to Freddy Galvis. It wasn’t deep, as it skipped off the top of the wall in left-center field before clearing the wall, but it counted.

Lourdes Gurriel Jr. then connected on a home run immediately after to make it back-to-back jacks for the Blue Jays. Even though Lucchesi had allowed just two hits and pitched brilliantly for nearly his entire outing, the score jumped to 3-3 in the blink of an eye.

“It sucks to give up three runs when you’re throwing the ball like that,” said manager Andy Green. “Outside of just sequencing those three things together, there’s no scenario where he was just going to give up those kind of runs today. I would have loved to see him get a win today. He pitched really well.”

Green eventually lifted Lucchesi with two outs in the seventh inning to set up Matt Wisler against Gurriel, which avoided a rematch. The home runs counted for two of just three hits allowed by Lucchesi, while his 11 strikeouts were balanced by a lone walk.

Padres power leads the way

Renfroe's decisive blast was his 12th home run of the season, and he remains on pace to take a run at his career high of 26, which he achieved in both 2017 and ‘18.

The ball only traveled 361 feet after leaving Renfroe’s bat with an exit velocity of 92.6 mph, according to Statcast, but he pulled it just far enough down the left-field line to sneak over the wall.

“All of those at-bats, when you think about the big homers, whether it’s off Kenley Jansen or [Jacob] deGrom, it’s choked up, it’s a battle, it’s short strokes,” Green said. “He got jammed. That gives you an indication of how much power he actually has right there. It’s aggressive.”

Renfroe’s blast was set up by a Manny Machado walk and a subsequent throwing error by Blue Jays reliever Daniel Hudson, who fielded a comebacker and missed his throw to second base. As the ball rolled into center field, Machado scampered to third base and there remained just one out, instead of what could have been an inning-ending double play.

Earlier in the game, Austin Hedges opened the scoring with a solo home run in the third, and Greg Garcia tacked on a solo shot of his own in the fifth inning with a laser off the facing of the second deck in right.