NEW YORK -- Blue Jays starter Trent Thornton was greeted with an uphill climb in Sunday’s 8-3 loss to the Yankees at Yankee Stadium, adding another wrinkle to a season that’s seen the 25-year-old succeed, struggle and adapt along the way.

Thornton followed opener Wilmer Font in the second inning, but the Yankees had already jumped out to a 4-0 lead. The rookie right-hander allowed a pair of runs in both the second and fifth innings, ending his day with four allowed over five innings on five hits, striking out three.

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The line wasn’t perfect, but manager Charlie Montoyo was encouraged by some clear signs of growth in Thornton, particularly when it came to how he responded following a second-inning home run.

“That’s good to see. He couldn’t do that at the beginning,” Montoyo said. “He’s growing. He’s growing up through the season. Now he knows that if he comes out and relaxes, he’s going to get out of trouble and he did today against a good lineup.”

Thornton was originally scheduled to come in for the start of the third inning, with the Blue Jays hoping to get at least a full two innings from Font, which he’s done in 14 of his 20 appearances since joining the club. Font couldn’t do it this time, which meant that Thornton needed to get ready quicker. This was an adjustment that he says he needs to make more efficiently next time, but it’s also one that’s understandably uncomfortable for a starting pitcher.

It wasn’t the plan going into the season, but Thornton has been the one constant in Toronto’s 2019 rotation. With injuries to Matt Shoemaker, Ryan Borucki and the since-released Clayton Richard, plus the trades of Marcus Stroman and Aaron Sanchez, Thornton holds a comfortable team lead in starts (29) and innings pitched (149 1/3) with one start likely remaining.

“I’m just starting to finally execute pitches a little bit better,” Thornton said. “I have a new changeup and a new curveball. The changeup was good today, the curveball not as good. I didn’t throw it quite as much. I’m learning how to pitch and how to set hitters up a little bit better.”

The results have been what you’d expect from a rookie with Thornton’s impressive raw talent. When he is on, he looks very sharp, with a hammering curveball that’s been effective and a fastball that averages 92.9 mph and was up to an average of 94.1 mph on Sunday, according to Statcast. There have been inconsistencies and ugly starts, but also stretches like his last seven outings entering play on Sunday, during which he’d posted a 3.03 ERA.

The Blue Jays’ bats were quiet behind Thornton, with the exception of Billy McKinney. The lineup combined for 15 strikeouts after striking out 15 times in Saturday’s loss as well, but they still managed to wedge in another MLB rookie record along the way.

McKinney’s 10th home run of the season, a two-run shot in the top of the seventh, gave the Blue Jays six rookies with 10 or more home runs in 2019, a new Major League record that was previously held by the 1958 Giants. McKinney joined Vladimir Guerrero Jr., Bo Bichette, Cavan Biggio, Danny Jansen and Rowdy Tellez. In the ninth, McKinney launched his second home run of the day to right-center field, giving him his first career multihomer game in the Majors.