Towers allowed four hits over six innings in a 1-0 victory Saturday, striking out five and walking one. He retired his final 10 batters.
"Josh did everything we expected him to do," manager John Gibbons said. "He looks like he did two years ago. He's won a lot of games for us in the past, and I have told him all along that last year was just one of those years. Everything he did and tried backfired. I told him to forget about it and bounce back. There is every indication that he has done that."
After going 13-12 with a 3.71 ERA in 2005, Towers dropped to 2-10 with an 8.42 ERA last year.
"Everybody has been real supportive of me," Towers said. "My first goal this year was to make the team."
Towers' first start of the season is scheduled for April 8 at Tampa Bay.
Closer B.J. Ryan, who hadn't pitched since March 11 because of lower back problems, allowed one hit and struck out two in a scoreless ninth.
"It was good to get out there in a game before we left and get an inning under your belt," Ryan said.
John Thomson, who was competing to become the No. 5 starter, was put on the disabled list. The right-hander pitched only 80 1-3 innings last year because of a right shoulder injury and blister problems on his throwing hand, and his velocity was down this spring.
Victor Zambrano, another former Met, earned a bullpen spot when Toronto added him to the major league roster Friday.
"I feel that I have been consistent in my job every day," Zambrano said.
Zambrano, coming back from elbow ligament-replacement surgery, had a 2.29 ERA in spring training, striking out 14 and walking 10 in 19 2-3 innings.
"Victor adds strength to our bullpen," Gibbons said. "I can see him coming out in the middle of a game. You never know what he might work his way into. He's got strikeout ability and has big guts."
Bobby Livingston, slated to open the season in the minor leagues, started for Cincinnati and allowed two hits in three shutout innings. Toronto got the only run in the fourth off Tom Shearn when Frank Thomas singled, pinch-runner John Ford-Griffin stole second and Alex Rios singled.
Joey Votto, who was born in the Toronto area, had two hits for Cincinnati. He was 10 when the Blue Jays won their second straight World Series in 1993.
"I stayed up and got to watch Joe Carter's homer run," Votto said. "We drove all around Toronto with my folks honking the horn. I was let down, though, after the strike because I thought they had a chance to win a third straight."
Toronto returned C Sal Fasano to its minor league camp. LHP Davis Romero (left shoulder) and Thomson (right shoulder) were placed on 15-day DL, and the Blue Jays purchased the contracts of 1B/OF Matt Stairs and Towers from Triple-A Syracuse. ... The game drew a spring-training low home attendance for Toronto of 2,314 but was the swiftest at 1 hour, 51 minutes. ... Reed Johnson doubled and ended spring training with a .438 average and a 13-game hitting streak.