TORONTO -- Gary Matthews Jr. did not even know his play allowed the go-ahead run to score.
After Mench singled in the sixth, Matthews hit a comebacker to reliever Jason Frasor, whose throw to first hit Matthews on the back of the helmet. The ball ricocheted near the stands and Matthews collided with Shea Hillenbrand at first, allowing Mench to score all the way from first.
"I just didn't know," Matthews said when asked if he knew Mench scored.
Matthews collapsed to the turf and stayed down for a couple of minutes. He wasn't removed for a pinch-runner, but was replaced in center field to start the bottom of the inning.
Texas manager Buck Showalter said he didn't like the look in Matthews' eyes.
Matthews said he might get a CT scan, depending on how he felt later.
"I'm feeling better now. I was a little sleepy for a while," Matthews said.
Joaquin Benoit and four relievers combined on a six-hitter and Adrian Gonzalez homered as Texas won for the fifth time in six games.
"They pretty much shut us down," Toronto manager John Gibbons said. "We didn't get much off today. That's what it came down to."
The Blue Jays have lost two straight after winning their previous three.
Phil Nevin didn't play for Texas. Acquired a day earlier from San Diego in a trade for Chan Ho Park, Nevin arrived at the Rogers Center just before game time. Manager Buck Showalter said Nevin will be the DH on Sunday.
Benoit (3-1) allowed two runs -- one earned -- and five hits, while striking out six and walking three in his third start of the season. Kevin Gryboski got the last out of the sixth, Brian Shouse worked the seventh, Kameron Loe the eighth and Francisco Cordero pitched the ninth for his 26th save in 32 chances.
Benoit thinks he'll be put back in the bullpen if the Rangers acquire a pitcher before Sunday's 4 p.m. EST non-waiver deadline.
"I really don't think about if I'm going to be in the rotation or not because a lot of things can happen before tomorrow. If something happens I'll be in the bullpen," Benoit said.
Benoit allowed the first three batters he faced to reach. Russ Adams singled, Frank Catalanotto doubled and Benoit hit Vernon Wells with a pitch.
Hillenbrand followed with a grounder to second baseman Alfonso Soriano, who threw to first to get Hillenbrand. Gonzalez, the first baseman, attempted to throw out Wells at second, but his throw sailed into left and allowed Catalanotto to score.
Rod Barajas hit a sacrifice fly in the second, cutting Toronto's lead to 2-1.
Gonzalez tied it with a solo shot off Frasor (1-5) in the sixth.
Toronto starter Dustin McGowan, making his major-league debut, allowed just one run and two hits in five innings. McGowan, a top pitching prospect, replaced Ted Lilly in the rotation. Toronto placed Lilly on the 15-day DL with biceps tendinitis.
Toronto second baseman Orlando Hudson made a spectacular play in the eighth when he snared a liner off the bat off Mench while diving to second to double off Soriano. ... McGowan struck out six, the most ever by a Blue Jays pitcher making his major league debut.