"I just tried not to screw up," said Frerotte, a 32-year-old veteran.
Culpepper left late in the second quarter with a bruised back after his second rushing TD gave the Vikings the lead for good. He was scheduled to have his back examined Sunday night in Minneapolis.
Culpepper said he was in too much pain to return to the game Sunday, but expects to play in Week 4 at home against San Francisco.
"Do I look hurt?" Culpepper asked as he limped away from Minnesota's locker room. "I thought I looked cool, like Fred Sanford."
Minnesota (3-0), with three victories in the NFC North, is off to its best start since winning seven games to start the 2000 season. The past two years, the Vikings were a combined 11-21.
"I think it's big because we've been on the low end of the stick," said Randy Moss, who caught three passes for 85 yards despite back spasms. "Being 3-0 in the division gives us the confidence that we can be a playoff team. We're not cocky about being 3-0, but we're confident all the hard work we put into the offseason is paying off."
The Lions (1-2) have lost to Minnesota and Green Bay since beating Arizona in the opener. They face tough games at Denver and San Francisco the next two weeks.
"This team is learning that we can beat a team like Arizona that is trying to improve, just like us, but now we are in a stretch of playing four playoff-contending teams in a row," Detroit coach Steve Mariucci said.
Minnesota outscored Detroit 23-3 after trailing 10-0 late in the first quarter.
Corey Chavous intercepted a poorly thrown pass from Joey Harrington in the end zone with 4:52 left. With just under two minutes left, the Lions were unable to score on two plays from Minnesota's 1 and two plays from its 2.
Culpepper didn't return after linebacker Wali Rainer hit him in the end zone on his 2-yard run that put the Vikings ahead -- for good -- 13-10 late in the second quarter. Culpepper was 7-of-13 for 105 yards.
"I guess it's part of the game, but I thought he could've pulled up when he saw I was in the end zone," said Culpepper, who's 6-0 against Detroit as a starter.
When Culpepper returned in the third quarter with a gray T-shirt and football pants on, the Vikings didn't need him to stay unbeaten. Frerotte, who has played for five teams including the Lions, was 8-of-19 with one interception to go along with his TD.
Minnesota's Moe Williams had 95 yards rushing and 54 yards receiving.
Culpepper's first rushing TD -- the 23rd of his career -- moved him past Fran Tarkenton for the most by a Vikings quarterback and pulled Minnesota within four early in the second quarter.
Harrington injured his right index finger in the second quarter when he hit center Dominic Raiola's helmet after throwing a pass. Harrington played the second half with his index and middle fingers taped together on his throwing hand. He was 24-of-42 for 235 yards with three interceptions.
"Part of my index finger went one way and part went another," Harrington said. "But I felt like I actually threw the ball better in the second half, so I might need to dislocate it more often."
Three big plays helped the Vikings win: Williams ran 61 yards from Minnesota's 3 to set up Culpepper's go-ahead score; Frerotte threw a 72-yard pass to Moss to set up Aaron Elling's 21-yard field goal just before halftime; and Frerotte's second 72-yard pass -- to Kelly Campbell -- gave the Vikings a 23-13 lead in the third.
"We didn't panic when Gus came in," Campbell said. "We knew we wouldn't miss a beat because he's a good quarterback."
Detroit finished poorly after a strong start.
On the opening drive, Harrington ran for a career-long 15 yards to set up Shawn Bryson's 5-yard TD run. Jason Hanson's 27-yard kick gave Detroit a 10-0 lead with 52 seconds left in the second quarter.
- Detroit's Eddie Drummond (sprained ankle), Andre Goodman (dislocated shoulder), Ray Brown (chest) and Shawn Jefferson (ribs) left with injuries.
- Minnesota's Billy Lyon left with a strained calf.
- Detroit's Charles Rogers caught six passes for 54 yards.
The Associated Press News Service
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