CLEVELAND -- Guardians pitching coach Carl Willis could notice his young starter Gavin Williams was getting frustrated.

A week ago, Williams had turned in his fourth consecutive start of five or fewer innings. In that span, he hadn’t given up more than five hits or two runs in a single outing. But he noted on multiple occasions that he was trying to be too fine with his pitches, which ran up his pitch count and caused him to exit each start much sooner than he would like. That’s when Willis stepped in to give him a little advice, and the results led to a one-hit, 12-strikeout performance in the Guardians’ 3-1 loss to the Blue Jays on Monday night at Progressive Field.

The guidance was rather simple. Willis wanted to remind Williams just how impressive his numbers were if you excluded the 14 walks in his previous 18 innings. When his pitches were going over the plate, he was seeing the results he wanted.

“He’s doing all of this and he’s not giving up very many hits or very many runs,” Willis said. “It’s been a fast path for him here, and I think he’s still giving a little too much credit to Major League hitters. They deserve credit, but a little too much. … Kind of challenged him to be a little more aggressive, and I think we saw the results of it tonight against a really good-hitting club.”

It was clear from the first inning that Williams had a little extra in the tank. He struck out the first two batters he faced on 97.1 mph and 96.6 mph heaters. After a double by Vladimir Guerrero Jr., Williams settled back in to fan George Springer on an 85.9 mph slider.

“From the start, I was just trying to throw it over the plate,” Williams said. “I don’t think I was being too fine today.”

The 24-year-old righty didn’t slow down after the first. By the time he finished the fifth inning, he already had racked up 10 strikeouts. Williams ended his night after seven frames and he became the first rookie pitcher in Cleveland history to have at least 12 strikeouts while allowing no more than one hit. It was the most strikeouts in a start by a Cleveland rookie since Luis Tiant fanned 12 on Aug. 18, 1964.

“His fastball was electric today,” Guardians catcher Bo Naylor said. “I feel like I could’ve just only called fastballs and it would’ve played really well.”

Of Williams’ 12 strikeouts, seven were recorded on his heater. He threw 52 four-seamers, which induced 25 swings. The 12 whiffs he got on those hacks were the most he’s had in a start so far in his career.

His fastball has been his calling card since he was drafted, consistently sitting in the upper 90s and occasionally seeing triple digits flash on Minor League radar guns. His fastball spin isn’t overwhelming, considering he ranks in just the 39th percentile in that category according to Baseball Savant. But the extension he has ranks in the 99th percentile, causing his heater to look even faster.

“He doesn’t have exactly the ride that you hear about,” Willis said. “I mean, it’s above average, but it’s not well above average. There’s velocity. His delivery, he’s a tall guy with long limbs, so he has some deception in terms of hiding the baseball before it’s released and he can create some angles, as well.”

Williams is starting to establish why he was the team’s No. 1 prospect, according to MLB Pipeline. In his debut in June, he was a little rattled making the transition to the big leagues. In his next outing, he wasted no time getting comfortable on the rubber, going seven scoreless innings with one hit, one walk and six strikeouts. It took some time for him to again look like that pitcher who took the ball on June 27, but he’s had to endure a crash course in pitching in the Majors, as he was abruptly thrown into the big league rotation after making just nine Triple-A starts because the Guardians suffered some injuries.

And with a little guidance from Willis, it’s abundantly clear -- if it wasn’t already -- that Williams’ stuff plays at the big league level.

“I think he realizes he belongs,” said DeMarlo Hale, who was filling in as manager for the suspended Terry Francona. “It’s really a natural growth that he’s going through. … He’s got that slow heartbeat and he goes about trying to execute pitches, and tonight was just outstanding.”