TORONTO -- The home runs were flying out fast, but Wilson Betemit's grounder was the biggest hit of the night.
"That was huge," Orioles pitcher Tommy Hunter said. "He had a hell of a game."
The switch-hitting Betemit is typically better from the left side, but he came through from the right side against veteran lefty Darren Oliver (0-1).
"Wilson has had a couple of big hits for us right-handed," Orioles manager Buck Showalter said. "I know exactly what (Blue Jays manager John Farrell) is thinking. I'd have done the same thing. (Betemit's) better side is left-handed."
Farrell instructed Oliver to pitch around Matt Wieters to get to Betemit, but the strategy failed.
"We probably should have faced Wieters instead of Betemit. Maybe I might have had better luck," Oliver said.
Darren O'Day (1-0) worked one inning of relief for the win and Jim Johnson closed it out for his third save as the Orioles opened a 10-game road trip, their longest of the season, by winning for just the sixth time in their past 35 games in Toronto -- a streak that dates to 2008.
"Here, playing in our division, it was important to start this road trip off pretty well," Adam Jones said.
Baltimore improved to 4-4 in its past eight games at Rogers Centre.
The teams combined for seven home runs, all solo shots.
"It was home run derby out there tonight," Jones said. "A lot of balls left the ballpark."
Robert Andino, Jones and Nolan Reimold connected for the Orioles, while Edwin Encarnacion, Yunel Escobar, Kelly Johnson and Colby Rasmus went deep for the Blue Jays, who doubled their season home run total in one game.
"Just about all of those were mistakes and that's where they should have been hit," Showalter said. "This is a big, strong man's league and you make those mistakes, they're not singles and doubles, they're going to end up where the grass doesn't grow."
All of Toronto's homers came against Hunter, matching his career high.
"Thankfully nobody was on base for any of them," Hunter said.
Hunter also allowed four homers in an Aug. 13, 2010, start against Boston.
Baltimore trailed 5-4 to begin the eighth against Blue Jays reliever Jason Frasor. Reimold led off with a single and J.J. Hardy struck out before Oliver replaced Frasor. Reimold stole second and went to third when Nick Markakis reached on an infield single. Jones struck out and Wieters walked to load the bases for Betemit, who grounded a first-pitch single to center, scoring Reimold and Markakis.
"I had a good pitch to hit," Betemit said. "He threw me a fastball right down the middle."
Reimold gave the Orioles some insurance with a homer off Casey Janssen in the ninth, his second.
Markakis' sacrifice fly gave Baltimore a 1-0 lead in the first, but Toronto answered in the bottom half on Kelly Johnson's one-out homer.
Markakis doubled and scored on a single by Jones in the fourth, but Toronto tied it in the bottom half when Reimold missed Adam Lind's liner to left for an error, allowing Jose Bautista to score from first.
"The lights are tough," Reimold said. "I ran to where I thought it was and it ended up being a little bit in front of me. I just botched it."
The relay throw home beat Bautista, but he evaded Wieters' tag as he slid in, then reached back to touch the plate.
Baltimore reclaimed the lead on Andino's homer to center in the fifth, his first, before solo shots from Rasmus and Escobar in the bottom half, the first for each, put the Blue Jays back on top.
Blue Jays starter Brandon Morrow couldn't hold the lead through the sixth, giving up a homer to Jones, his second, but Toronto promptly answered on Encarnacion's one-out shot in the bottom half, his second, to take a 5-4 lead.
Morrow allowed four runs and six hits in seven innings. Hunter gave up five runs, four earned, and six hits in six-plus innings.
Jim Johnson has converted 11 straight save opportunities dating to 2011. ... Toronto placed closer Sergio Santos on the paternity list and recalled LHP Evan Crawford from Double-A New Hampshire. Santos flew home to California on Wednesday after earning the save in Toronto's 3-1 win over Boston to join his wife for the birth of their second son. He could rejoin the team as early as Saturday. ... Baltimore's Mark Reynolds, who has struggled with his defense, made his first start at DH with Betemit taking his place at 3B. ... Orioles RHP Jake Arrieta will start Monday in Chicago, pushing LHP Wei-Yin Chen back one day to Tuesday. Showalter said he wanted to split up lefties Chen and Brian Matusz, who starts Sunday.