TORONTO -- For Trent Thornton to take the next step in 2020, beats per minute will be as important as miles per hour.

The young right-hander flashed plenty of potential in 2019, becoming the unexpected leader in starts and innings pitched for the Blue Jays, but found himself back in a competition this spring and summer after three veteran starters were brought in. He’d already won a job well before Wednesday’s exhibition finale, a rain-shortened game against the Red Sox that the Blue Jays led 2-0 when it was called, but it was a sharp performance to carry into the regular season.

Pitching coach Pete Walker has seen plenty of Thornton and his deep, six-pitch mix, but pointed to Thornton’s breath and heart rate on the mound, not his mechanics, as the real key.

“I still think we’ve got to calm him down a little bit. He’s awesome,” Walker said. “He’s got great potential, great Major League ability. He tends to overthrow at times. We talk about it all the time. When he can settle down a little bit more, I think he’s really going to excel and take off.”

In doing that, Thornton hopes to become a more efficient pitcher. The 26-year-old spent nearly the entire season in the rotation last year, but worked beyond six innings just three times. If Wednesday was any indication, that number’s about to climb, as he needed just 43 pitches to breeze through three shutout innings.

Thornton leaned heavily on his cutter against the Red Sox, and it was working. One of his best came in the bottom of the second against Xander Bogaerts, who Thornton struck out swinging on the outside edge as the cutter ran away from him. Thornton’s splits were fairly even in his rookie year, but there’s optimism that he could become tougher on lefties, in particular.

The Blue Jays have tipped their hand on how their rotation will line up beyond Hyun Jin Ryu on Friday and Matt Shoemaker on Saturday against the Rays. Tanner Roark is scheduled to throw live BP during an optional workout, meaning his regular rest days would put him into the No. 4 slot. Thornton’s regular rest, after today, would line him up with that Sunday series finale in Tampa as the No. 3.

Following Thornton was right-hander Shun Yamaguchi, who’s also been considered for that No. 5 job, but is likelier to open the season in a hybrid or swingman role, as he’s both stretched out, but experienced pitching in shorter stints. Yamaguchi turned in a clean inning of his own, and has already come a long way since his Spring Training debut way back in February, when he was still adjusting to the MLB ball and style of play.

“In a year like this year, that’s very important for us,” manager Charlie Montoyo said prior to the game. “He can do both, and he’s fine with both.”

The only offense either team produced before the rain hit was a massive, two-run home run by Vladimir Guerrero Jr., which soared well over the billboards atop the Green Monster and out of the stadium. It’s an important final note for Guerrero to end his Summer Camp on after making little threatening contact in Toronto. There’s no questioning Guerrero’s talent, but his ability to lift the ball and avoid grounders in 2020 will be one of the most important variables in this entire lineup.