Maicer Izturis hit a solo homer in the fifth for Toronto, on its longest winning streak since a 10-game run late in 2008. The Blue Jays, 14-4 this month, are one victory from matching the franchise record. Toronto had 11-game winning streaks in 1987 and 1998.
"It's been a great run and hopefully we can continue," Bautista said.
The Blue Jays (37-36) are above .500 for the first time since last July 29, when they were 51-50.
Bautista traded angry words with O'Day after striking out to end the seventh inning Friday, stranding a runner at second base.
On Saturday, the Blue Jays slugger renewed the argument, yelling at O'Day while rounding the bases after his pivotal home run.
"I told him just to keep talking like he was yesterday because he kind of ran his mouth a little bit after he struck me out," Bautista said. "I don't know where that came from but I didn't appreciate it. I let him know that yesterday and that's a little reminder today."
O'Day declined to talk about his spat with Bautista, while Orioles manager Buck Showalter chalked it up to a clash of competitive personalities.
"Darren is a competitor, he likes to compete in those situations," Showalter said. "Sometimes he wins, sometimes Bautista wins. You've got two great, talented athletes competing out there and they both take it personally."
Orioles starter Miguel Gonzalez left after Munenori Kawasaki hit a one-out single in the bottom half. O'Day came on and got Rajai Davis to ground into a fielder's choice, but Bautista followed with a two-out homer just inside the left-field foul pole on a 3-2 pitch.
"I made a terrible pitch," O'Day said. "If I make a good pitch, he's probably out."
Bautista, who homered for the 16th time this season, said he wasn't sure his drive was going to stay fair.
"I had no idea it was going to go out, either," Bautista said. "I knew I hit it well but I didn't know if it had enough."
The homer was the first allowed by O'Day since May 22, when Yankees infielder David Adams took him deep.
Oliver (3-1) worked one inning and Casey Janssen finished for his 17th save in 18 chances.
Gonzalez (5-3) allowed three runs and three hits in 7 1/3 innings. The right-hander, who won his previous three starts, lost for the first time since May 3 at the Los Angeles Angels.
"He was outstanding today," Showalter said. "He pitched really well. I was really proud of him."
It's been a busy week for Gonzalez, who left the team Monday for the birth of his first child, a daughter, and was activated off the paternity list Friday.
"I was supposed to throw a bullpen three days ago but it didn't happen," Gonzalez said. "I was back home with the family."
Izturis put the Blue Jays back in front by homering on the first pitch of the fifth.
Baltimore left the potential tying run stranded at third base in the seventh but knotted it at 2 in the eighth on Teagarden's one-out homer.
Blue Jays starter Chien-Ming Wang left to a standing ovation after giving up one run and five hits in 6 1/3 innings. The right-hander, who walked none and struck out two, has a 2.61 ERA in three starts with Toronto.
"That's three really good ones," manager John Gibbons said. "He shut down a good hitting team. I know he feels good, he's a part of it now. He's given us a big boost, that's for sure."
Bautista is one home run away from 200 for his career. ... Blue Jays RHP Kyle Drabek (elbow surgery) is set to begin a minor league rehabilitation assignment with Class-A Dunedin on Saturday. ... Orioles C Matt Wieters got the day off, while Chris Davis started at DH. He doubled and scored a run, but struck out to end the game. ... Baltimore RHP Freddy Garcia is expected to start Sunday's series finale against RHP Josh Johnson, meaning LHP Zach Britton will start for the Orioles against Cleveland on Monday.
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