TORONTO -- In what has been an up-and-down season for rookie Blue Jays hurler Trent Thornton, his performance in Sunday’s series finale against the Yankees at Rogers Centre was among the highlights.

In Toronto’s 1-0 loss to New York, the 25-year-old right-hander was perfect for four innings before allowing back-to-back doubles in the fifth, but he stranded runners at third base in both of his last two frames. Thornton completed six innings, allowing one run on three hits, walking one batter, hitting another and striking out six.

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“What helped him with the success this time around was in the counts [we were behind], we made our pitches, we didn’t walk them,” catcher Reese McGuire said. “We made a pitch right there and got a ball in play, and more times than not, it was either a popup or a ground ball. When he was getting ahead, that’s what we wanted, but then when he fell behind, it was also in those moments he made his pitches.”

After failing to get through four innings in his most recent start versus the Rays on Tuesday, the young hurler had everything working against the American League East leaders, using a good mix of his four-seam and two-seam fastballs, to go with a cutter he went to more than usual, along with his splitter and slider. He entered the matchup with a 7.85 ERA in 47 innings against divisional opponents and made a marked improvement.

“The cutter was definitely a big pitch for me today,” Thornton said. “It was kind of coming out of the fastball tunnel and it was biting at the end. I thought Reese did a great job back there, called a great game. There are a lot of positives to take out of that.”

Added McGuire: “Mixing the two-seamer in there makes his four-seam better, and then the cutter off of the two-seamer or the four-seamer is always a great go-to pitch in any count. And he really had everything working for him, so we just mixed it up.”

The six strikeouts for the freshman pitcher moved Thornton into sole possession of second place among all rookies, with 110 on the season. The 6-foot, 195-pound hurler is behind only San Diego’s Chris Paddack, who has fanned 115 batters this year.

“He was throwing more strikes and he was commanding the zone, that was the key,” Blue Jays manager Charlie Montoyo said. “Against a great lineup, he was really good. And McGuire does a great job behind the plate, framing pitches and stuff, he did a good job.”

Sunday’s start was Thornton’s second since returning from a stint on the injured list with right elbow inflammation, working in a five-man rotation for the first time in his professional career this season. It was an encouraging sign for the future of a young club with a strong offensive core and question marks surrounding its staff.

“There’s a little of everything to take into consideration, when your whole career in the Minor Leagues, especially with the Astros, we were on a six-man rotation, we were piggybacking,” Thornton said. “For me, my first year in the big leagues is the first time I’ve ever been in a five-man rotation. It’s going to take a little bit of adjusting. But any baseball player’s got to make adjustments on a day-to-day basis, so it’s just part of the game.”

Despite Thornton’s impressive efforts, Masahiro Tanaka was even better for the visitors, shutting out the Blue Jays for eight-plus innings while allowing just three hits. One of them was to Bo Bichette -- who had two singles in the matchup -- extending the 21-year-old infielder’s career-opening on-base streak to 14 games.

“We played a really tough game today,” Thornton said. “We were in every at-bat until the very last one. Unfortunately we lost today, but there are a lot of positive things to take out of that.”