"He did a great job," Toronto manager Cito Gaston said. "It was just what we needed. He pitched a great game."
Richmond (5-3) allowed five hits and retired his last 13 batters. The 29-year-old rookie was 0-3 with a 5.81 ERA in his previous five starts.
"I was anxious to get out there," Richmond said. "I was working on a few things. I mentally prepared myself and it worked nicely."
Jayson Werth homered for the NL East-leading Phillies, who fell to 13-18 at home. The defending World Series champions are a major league-best 23-9 on the road.
"Over 162 games, there are some when you don't have much life," Phillies manager Charlie Manuel said. "We just couldn't get going tonight."
Jamie Moyer (4-6) gave up six runs and 10 hits in six-plus innings. The 46-year-old, soft-tossing lefty had pitched better recently after a tough start. Moyer had a quality start in four of his last five outings before getting roughed up by the Blue Jays. His ERA rose to 6.35.
"It was poor location more than anything else," Moyer said.
B.J. Ryan, Toronto's former closer, walked the bases loaded in the ninth and left with one out. Brandon League struck out Werth, and shortstop Marco Scutaro made an outstanding play on Pedro Feliz's hard one-hopper to end it.
Toronto gave Richmond all the runs he needed with a three-run first. Scutaro led off with an infield single and Hill followed with an RBI double. After Vernon Wells walked, Rolen singled in Hill.
Barajas homered to left-center to start the second, giving the Blue Jays a 4-0 lead. Hill hit his team-leading 15th in the seventh. Rolen connected later that inning off reliever Chad Durbin to make it 7-1.
Werth lined an opposite-field shot to right-center in the fourth. One batter earlier, Scutaro started a nifty double play on Raul Ibanez's hard one-hopper up the middle. Scutaro ranged to his left to field the ball and made a glove toss to second baseman Hill.
Richmond's previous high was eight strikeouts against Texas on April 23. The right-hander fanned six in the first three innings and issued one walk on the night. The Blue Jays are going to need more outings like this from Richmond and the rest of their patchwork rotation.
Toronto ace Roy Halladay and closer Scott Downs are headed for the disabled list Thursday, and starter Casey Janssen was placed on the 15-day DL before the game. The rash of injuries leaves the Blue Jays without their top five starters. Dustin McGowan, Shaun Marcum and Jesse Litsch are also on the DL.
Gaston instructed Richmond not to swing the bat his first couple times up and he didn't think twice about pulling him after eight innings instead of keeping him out there for a chance at his first complete game.
"We've got enough guys on the DL," Gaston said.
Despite a depleted pitching staff, the Blue Jays stayed five games behind first-place Boston in the tough AL East.
The Phillies are 2-10-1 in home series this season. Their only victories are against the lowly Washington Nationals. ... Rolen has a seven-game hitting streak. He's batting .517 (15-for-29) during that stretch. ... Hill, who bats No. 2 in the lineup, is two homers shy of matching his career best, set in 2007. ... Philadelphia's starters have a 5.38 ERA.