After completing his first eight passes, Cutler threw an interception that the Arizona Cardinals' Tony Jefferson returned for a touchdown late in the second quarter. Cutler made a vain attempt to tackle Jefferson and suffered what the team said was a hamstring injury that put him out for the day -- and perhaps longer.
Jefferson's touchdown opened the floodgates to what ended as a 48-23 victory for the Cardinals, who had been locked in a 14-14 tie before scoring two touchdowns in 52 seconds late in the half.
The Bears said nothing about how long Cutler might be out of action, but backup quarterback Jimmy Clausen, who finished the game, gave a hint by saying, "Guys have to step up when guys go down. That's the situation we're in right now."
It could be a dismal situation for the 0-2 Bears, who play three of their next four games on the road, starting next Sunday at Seattle.
Cutler's injury did not appear to be a hamstring when he landed on his shoulder and head after chasing Jefferson, and he never grabbed at his leg and did not appear to limp as he was helped off the field. Coach John Fox said simply it was a "pulled hamstring," and gave no indication of the severity.
"I felt the air was deflated a little bit (when Cutler went out), but guys did a great job of (saying), 'Let's pick up the tempo,'" Clausen said.
Nonetheless, Chicago's only scoring the rest of the game came on three field goals by Robbie Gould.
Arizona, meanwhile, is off to a 2-0 start behind quarterback Carson Palmer, who has won 15 of his last 17 starts. Palmer completed 17 of 24 passes for 185 yards, including four touchdowns, three of them to wide receiver Larry Fitzgerald. Fitzgerald caught a game-high eight passes for 112 yards.
Fitzgerald has been one of the NFL's best receivers for more than a decade, but surprisingly this was his first three touchdown regular-season game.
Even Arians said, "That's hard for me to believe."
Until Cutler's injury, it appeared that the Bears might be able to stay with the Cardinals, who jumped on top when David Johnson returned the opening kickoff 108 yards for a touchdown.
Johnson, whose kickoff return was his first touchdown in the NFL, scored his second later in the game on a 13-yard run.
Early on, the teams exchanged mistakes, with Arizona twice leaving Chicago receivers uncovered, and the Bears helped the Cardinals offense move the ball by committing long pass interference penalties. That led to a tie at 14 before Fitzgerald's first touchdown. The Jefferson interception/touchdown came two plays after the ensuing kickoff.
Big penalties were the theme of the day for the Bears, who were penalized 14 times for 170 yards, matching a 71-year-old team record for penalty yardage in a game. Cornerback Kyle Fuller, beaten both for penalties and touchdowns, eventually was benched.
"You'd like to add up all the yardage we got on interferences because they don't show up on the stats," said Cardinals coach Bruce Arians, referring to the fact his team totaled just 300 yards on offense. "It felt like a whole lot more than that."
"Downfield penalties were a huge issue," Fox said. There are "a lot of things we have to clean up and fix. We gave up 170 yards in penalties (mostly) on downfield throws, and it wasn't a mystery we were going to see some of those."
If Clausen has to start next week at Seattle, it would be just his second start since his rookie season in 2010 with Carolina. He started one game for the Bears last December in the season's penultimate game, but suffered a concussion and did not play again.
NOTES: The Bears played without WR Alshon Jeffery (hamstring), who led the team in receiving yards and touchdowns a year ago and also in their opening day loss to Green Bay . . . RB Andre Ellington (knee), Arizona's leading rusher, also missed the game . . . Cards LB LaMarr Woodley went out of the game in the first quarter with a right shoulder injury . . . QB Jimmy Clausen, who joined the Bears as a free agent in 2014, appeared in four games last year, starting one in late December . . . Cards WR J.J. Nelson left the game in the third quarter with an injured right shoulder.