TORONTO -- Brad Mills knew he was only going to get one start before heading back to the minors. He made sure it was a good one.
Mills, a rookie left-hander, pitched seven innings for his first major league win, Lyle Overbay hit a three-run homer and the Blue Jays wrapped up a three-game sweep by beating the Orioles 5-0 on Wednesday night, Toronto's 12th consecutive win over Baltimore.
"[Mills] was making a lot of good hitters look foolish up there," Overbay said.
Called up to make a spot start after Toronto played a doubleheader in Detroit on Sunday, Mills was optioned back to Triple-A Las Vegas after the game. He may be gone, but he won't soon be forgotten by Blue Jays manager Cito Gaston.
"If we need a starter somewhere down the line, we know where to go get him," Gaston said.
Making his first start of the season and just the third of his career, Mills (1-0) allowed two hits, both singles, walked three and struck out four. The 25-year-old went 0-1 in two starts last season, both against the Philadelphia Phillies, giving up 12 runs in 7 2/3 innings.
"Last year didn't go the way I wanted to so it's great to come up here and prove to myself that I can pitch here and get outs here," Mills said. "I know I can pitch here."
Overbay said Mills showed a lot more poise than in his two 2009 starts.
"You could see he was a lot more confident," Overbay said. "The last couple of times he looked real tentative and he was scared of making a mistake. That's nothing out of the ordinary. I think everybody goes through that. I felt like he was a different pitcher tonight."
Brian Roberts lined a single to right on the soft-tossing lefty's third pitch of the game and was promptly erased on a double play. Mills didn't allow another hit until Jake Fox's two-out liner to left in the seventh.
Adam Lind went 3-for-3 with an RBI and an intentional walk for the Blue Jays, who have won five of six.
Toronto, which faces Baltimore six more times this season, is one victory from matching its club-record 13-game winning streak against Baltimore, set between April 11, 1999, and May 10, 2000.
"When we've scored a few runs, they've scored more and when we've been able to limit them in their runs, they've done better than us," Baltimore right-hander Jeremy Guthrie said. "That's what good teams do and they've played well against us this year."
Baltimore has lost five straight and is 2-11 since the All-Star break.
The Blue Jays, who lead the majors with 155 homers, have gone deep in 10 straight games and hit 25 homers in that span. Toronto has a league-high 40 homers in July.
It was the eighth shutout of the season for the Blue Jays and the seventh time the Orioles have been blanked.
Guthrie (4-11) allowed six hits in seven innings, walked one (intentional) and struck out three.
An error by Baltimore left fielder Corey Patterson gave the Blue Jays the lead in the second. Vernon Wells led off with a single and scored all the way from first when Lind lined a hit-and-run single through the hole at shortstop, with the ball clanging off Patterson's glove and rolling away.
"I came up and looked to check where the runner was," Patterson said. "At the last minute I looked up to see if he was going to third base and unfortunately it kicked away from me. I just missed it."
Toronto blew it open with a four-run eighth. Jose Bautista doubled off Koji Uehara and scored when Lind hit a two-out single against Will Ohman. Aaron Hill was walked intentionally to bring up Overbay, who lined a three-run drive to left-center, his 12th.
"He made a mistake," Overbay said. "It was a fastball, right down the middle. You've got to make him pay for it."
Blue Jays outfielder Travis Snider, who has not played since May 15 because of a sore right wrist, is expected to rejoin the team before Friday's game against Cleveland, replacing Mills on the roster. ... Baltimore's Ty Wigginton returned to the lineup after serving a two-game suspension for making contact with umpire Gary Darling in an argument last week. Orioles catcher Matt Wieters and left fielder Felix Pie were held out of the starting lineup. ... Blue Jays shortstop Yunel Escobar went 0-for-4, ending his hitting streak at 10 games.