A walk to Shannon Stewart followed. By the time the first inning was over, the A's were trailing 3-0, and it appeared the Oakland bullpen might be in for a busy night.
But as he did during spring training, Smith showed a poise that belies his inexperience. He delivered five scoreless innings after the first, kept his team close, and the A's rallied in the ninth inning to pull out a 6-3 victory at the Rogers Centre.
Smith, called up from Triple-A Sacramento to start in place of the injured Justin Duchscherer, said he was a bit in awe when he stepped onto the field for the first time and gazed up at the crowd.
He also had an adrenaline rush during that turbulent first inning.
"It was hard not to," Smith said. "But it really wasn't that different (from pitching in the minors), to tell you the truth. You're more aware of what's going on around you. But after that (first inning), it just felt like a normal game."
Smith wasn't the only one receiving congratulations in the A's clubhouse. Reliever Fernando Hernandez also made his big-league debut and was credited with the victory after throwing a scoreless eighth inning.
It was the A's second straight win to start this three-city road trip and bumped their record to 5-4.
In the big picture, manager Bob Geren was probably most pleased about Smith's outing.
Smith was one of six players obtained from the Arizona Diamondbacks in the Dan Haren trade, but he was one of the lesser heralded of the bunch. But A's front office officials talked highly of him even before he posted a 1.50 ERA in five spring training outings.
Smith, 24, issued five walks Wednesday but allowed just two hits over six innings with five strikeouts. He struck out Toronto's No. 3 hitter, Alex Rios, all three times he faced him.
And his first-inning adventures weren't all his own doing. With the bases loaded and 1-0 deficit, A's first baseman Daric Barton cut off a throw from center fielder Ryan Sweeney on Aaron Hill's sacrifice fly and threw wildly home, allowing a second run to score on the play.
"For a young guy to get out there and have a little bit of a rough inning, and have the defense make a mistake behind him and keep throwing zeroes up there, that's very impressive," Geren said of Smith.
The A's trailed 3-2 entering the ninth before rallying for four runs against Toronto relievers Jeremy Accardo and Brian Wolfe. Mark Ellis (4-for-5) tied the game with a run-scoring triple. Bobby Crosby added a two-run double as part of his three-RBI night.
Until the ninth, the A's had squandered several scoring chances, including a bases-loaded, no-out situation in the fifth.
"You've got to figure it's going to happen at some point," Crosby said. "We were getting guys in scoring position. You've got to keep working and hope somebody gets the job done."
Smith certainly seemed to earn another start. Duchscherer's next turn in the rotation would come Monday against the Chicago White Sox.
As for Hernandez, 23, the only A's pitcher who had yet to appear in a game this season, he was pinching himself when he entered in the eighth and faced Frank Thomas to lead off the inning.
He got Thomas to fly out to deep center field. Thomas had homered in three straight games entering Wednesday. Hernandez said he used to wear Thomas-endorsed baseball cleats as a youth growing up in Miami.
"I used to have that guy's shoes when I was a little kid," Hernandez said. "(Facing him) is something I can't describe. I was pumped. Real pumped."
Contact Joe Stiglich at email@example.com.