TORONTO -- Johnny Damon thinks the World Series champions have become "a really bad team."
The Red Sox, who have lost six of nine, play one more in Toronto before heading to New York for a three-game series.
"We're a really bad team right now," Damon said. "We need to win tomorrow. It's a must win. We need to get back to that stage where every game is a must win instead of just saying 'Oh, we'll be OK.' It's a different year."
Damon said the Red Sox are good enough to get back to the World Series, but they must get going.
"We were in trouble on that West coast swing, and we were in trouble these first two games here," Damon said. "New York's climbing. We have to start doing something or it could be a long summer. ... We have a big series this weekend. Whether or not the Yankees are going to overtake us or not, we can't let that happen."
Arroyo (4-1) had won nine consecutive decisions since the Chicago White Sox beat him last Aug. 15. He had not pitched since May 16 after dropping his appeal of a six-game suspension stemming from a game on April 24 when he hit two Tampa Bay batters with pitches.
"I wasn't rusty. I felt good," Arroyo said.
The 28-year-old right-hander, making his 100th major league appearance, allowed five runs -- two earned -- and six hits in six innings. He also hit two more batters.
"We're just struggling right now, and we have to get back on track," Arroyo said.
Boston, which had two errors and a passed ball, has lost the first two games of its six-game trip.
"We're struggling all around," David Ortiz said. "We're not hitting, we're not playing good defense. Sometimes our pitching is not there."
Russ Adams had two hits and scored two runs for the Blue Jays, who are 5-2 against Boston this season.
Lilly (3-4) allowed one run and four hits in 6 2/3 innings, his longest outing this season, and lowered his ERA from 8.82 to 7.59.
"I feel like I'm contributing and it's been a long time since I've done that," Lilly said.
Toronto took a 2-0 lead in the first. Arroyo hit the first batter, Reed Johnson, and Orlando Hudson reached on first baseman Kevin Millar's fielding error. After Jason Varitek's passed ball allowed the runners to advance, Gregg Zaun had an RBI single and Shea Hillenbrand hit into a run-scoring double play.
Consecutive doubles by Vernon Wells and Aaron Hill made it 3-0 in the third. Arroyo's throwing error to first in the fifth allowed Adams to score and Johnson to reach third. Hudson followed with a sacrifice fly for a 5-0 lead.
Bill Mueller, Trot Nixon and Mark Bellhorn hit consecutive singles off Lilly in the seventh, but Boston scored just one run, on Damon's RBI grounder.
Adams and Johnson hit consecutive doubles off John Halama in the bottom half.
Toronto 3B Corey Koskie had surgery to repair the broken right thumb and ligament damage sustained in a game last week. Koskie is expected to miss four to six weeks. ... The Red Sox had won 15 of Arroyo's previous 17 starts.