TORONTO -- Jack Flaherty pitched six innings to win his Baltimore debut, Ryan Mountcastle and Austin Hays each had four hits and the American League-leading Orioles beat the Toronto Blue Jays 6-1 on Thursday.

Mountcastle went 4-for-4 and scored twice and Hays was 4-for-5 with two RBIs as Baltimore took three of four from Toronto. The Orioles are 8-2 against the Blue Jays this season.

"Still a long way to go, but love the way we're playing," Orioles manager Brandon Hyde said.

Acquired from the St. Louis Cardinals on Tuesday, Flaherty (8-6) allowed one run and four hits. He walked two and struck out eight.

"It was fun," Flaherty said. "New energy, new everything. Sometimes that can be a little tricky but [catcher Adley Rutschman] was awesome back there."

Flaherty got a win against the Blue Jays for the second time this season. With the Cardinals, Flaherty overcame a career-worst seven walks to pitch five shutout innings and beat Toronto on April 1.

"I was definitely a different pitcher today than I was then," Flaherty said. "I was able to do a lot more things."

Toronto's Whit Merrifield led off the bottom of the first with a single and Brandon Belt walked, but Flaherty retired the next 15 batters in order.

He became the second Orioles pitcher to retire 15 or more consecutive hitters in his debut with the team since it moved to Baltimore in 1954 (Dave McNally retired 17 straight on Sept. 26, 1962). He also became the first Orioles pitcher with eight strikeouts and one or fewer earned runs allowed in his debut with the team since 1966 (Tom Phoebus).

"That was amazing," Mountcastle said. "He looked really good and had all his stuff working."

Baltimore extended its lead in the AL East to two games over the idle Tampa Bay Rays.

Toronto is 8-23 against the AL East and 52-27 against all other opponents.

Over the four-game series, Mountcastle went 11-for-13 with three walks, four doubles and six RBIs. He also scored five runs.

"I'm going to put a massive Rogers Centre banner in his locker just to remind him what it feels like to hit here," Hyde said jokingly. "It's the best I've ever seen him swing the bat, honestly, for a four-game set."

Information from The Associated Press was used in this report.