GLENDALE, Ariz. – Even on a very bad night for Rex Grossman, the Chicago Bears found a way to stay unbeaten. They can thank their defense, punt returner Devin Hester and Arizona kicker Neil Rackers for that.

Chicago, down 20-0 at halftime, returned two fumbles for touchdowns in the second half. Then Hester returned a punt 83 yards for a score with 2:58 remaining to take the lead and the Bears (6-0) overcame six turnovers by Grossman to beat the Cardinals 24-23 on a wild Monday night.

Matt Leinart, who threw two first-quarter touchdowns and finished 24-for-42 for 232 yards, coolly directed Arizona downfield at the finish.

But Rackers, a Pro Bowl kicker last season who connected from 41, 28 and 29 yards earlier in the evening, missed a 41-yarder to the left with 53 seconds left for what would have been the game winner for Arizona (1-5).

Anquan Boldin caught 12 passes for 136 yards and a touchdown for the Cardinals, who blew a late lead at home for the third time this season. Similar collapses occurred against St. Louis and Kansas City.

After Grossman threw his fourth interception, the Cardinals were trying to use up time. But Brian Urlacher stripped the ball from Edgerrin James and Charles Tillman scooped it up for a 40-yard return to cut Arizona’s lead to 23-17 with five minutes left.

Urlacher finished with 11 tackles, seeming to find his way to the ball on nearly every play as the Cardinals were making their final drives.

“First of all they weren’t blocking me, so that was easy,” Urlacher said.

On their next possession, the Cardinals were forced to punt. Hester caught the ball, broke a few arm tackles and sprinted upfield, scoring his second punt return for a touchdown this season and giving Chicago the lead for the first time all night.

In addition to his four picks, Grossman fumbled the ball away twice and struggled to hit receivers when he did manage to get the ball cleanly away, going 14-for-37 for 148 yards.

With their offense suddenly punchless, the Bears’ defense provided the points.

The first came when defensive end Mark Anderson broke through untouched and blindsided Leinart, forcing a fumble that Mike Brown returned 3 yards for a touchdown that cut the lead to 23-10 with two seconds left in the third quarter.

Chicago entered the game with five turnovers in five games, 10 fewer than their foes. But it was evident early that this would be a frightful night with the roof open for the first time in Arizona’s extravagant new stadium.

Four of the turnovers helped the Cardinals (2-4) to a 20-0 halftime lead in Arizona’s first Monday night appearance since 1999.

The Bears steamrolled into town on their best start in 20 years, bringing a fierce defense and an efficient offense that had blown out Seattle and Buffalo by a combined 77-13 score their previous two games.

But Leinart, in his second NFL start, ran the offense with precision and poise at the start, becoming the first rookie to throw a pair of first-quarter TD passes in his first two starts. This time, he did it without Pro Bowl receiver Larry Fitzgerald, sidelined with a hamstring injury, against a Chicago defense that had allowed two touchdowns all season.

Accustomed to the bright lights that came with three national championship game appearances at USC, Leinart was anything but intimidated. He was 5-for-5 on a 12-play, 77-yard touchdown drive on Arizona’s opening drive.

“He’s a good quarterback,” Urlacher said. “He’s young, we tried to throw a lot of stuff at him. He took care of the football, didn’t have any interceptions. But we made the plays when we had to.”