Chone Figgins drove in two runs for the AL West-leading Angels, who moved two games ahead of second-place Oakland.
Only 2½ weeks after the Blue Jays completed a three-game sweep of the Angels with an 18-inning victory -- the longest game in Toronto history -- the teams played their third straight extra-inning contest. This time, the winning and losing pitchers were reversed from the marathon game in Canada.
Orlando Cabrera greeted Pete Walker (5-4) with a leadoff double in the 11th, and Erstad lined an 0-2 pitch the other way to left-center.
Scot Shields (8-8) pitched two innings of one-hit relief for the victory.
Shea Hillenbrand capped a three-run eighth inning with a go-ahead RBI double and No. 9 hitter Orlando Hudson had two RBI, helping the Blue Jays take a 4-3 lead. But the Angels tied it in the bottom half.
Maicer Izturis singled with one out against reliever Vinnie Chulk, and Kennedy greeted former teammate Scott Schoeneweis with a single that put runners at the corners. Figgins used his superior speed to beat out a potential double-play grounder, allowing Izturis to score the tying run.
In a matchup featuring two of the AL's most talented rookie pitchers, Angels right-hander Ervin Santana took a 3-1 lead into the seventh against Gustavo Chacin before the Blue Jays took the lead.
Hudson chased Santana with an RBI single. Brendan Donnelly grazed Frank Catalanotto on the leg with a pitch, then gave up a bases-loaded sacrifice fly to Vernon Wells that tied the score 3-all.
Hillenbrand followed with a double that scored Hudson with the go-ahead run. Catalanotto tried to score behind him, but was erased by shortstop Cabrera's relay throw to Jose Molina. Third base coach Brian Butterfield argued the close play with umpire Ron Kulpa and was ejected.
Santana was charged with four runs -- three earned -- and six hits in six-plus innings. He has not allowed more than three earned runs in any of his last six starts.
Chacin allowed three runs and six hits in six innings, striking out four and walking three. The left-hander made his first start on the road since July 2, after going 5-1 in seven starts at Toronto.
The Blue Jays tied the score 1-all in the fifth with an unearned run, but the Angels regained the lead in the bottom half.
Kennedy bunted for a hit and continued to second on Chacin's errant throw. Figgins drove him in with a single. After a two-out single by Erstad, Toronto manager John Gibbons went against the book and ordered an intentional walk to AL MVP Vladimir Guerrero -- with runners at first and second.
Chacin got behind Bengie Molina 3-1, but came back to retire him on a flyout.
The Angels, playing their first home game since the death of Gene Mauch on Aug. 8, observed a moment of silence in memory of the former Angels manager and honored him with a video tribute in the third inning. Mauch guided the team to division titles in 1982 and 1986, and his .533 winning percentage is still the highest in franchise history. ... Angels RHP Paul Byrd will not make his scheduled start Tuesday because of back spasms. LHP Joe Saunders will be promoted from Triple-A Salt Lake to make his major league debut. The 24-year-old Saunders was the 12th overall pick in the June 2002 draft out of Virginia Tech.