Peyton Manning was cool and confident, lofting passes to teammates as if they were buddies in his backyard.

Whether it was third or fourth down, in the second or fourth quarter, the 39-year-old Manning showed he still has it.

Manning converted a fourth down with a 45-yard touchdown pass to Demaryius Thomas with 5 seconds left in the first half. Then he threw an 11-yard scoring pass to Owen Daniels on a third down with 2:28 remaining, lifting the Denver Broncos to a 24-12 victory over the Detroit Lions on Sunday night.

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Manning was 31 of 42 for 324 yards with two TDs and an interception. The five-time MVP joined Brett Favre as the only players in NFL history with at least 6,000 completions.

The last time the Broncos (3-0) won their first three games was in 2013, when they reached the Super Bowl.

Manning was sacked only once after he was sacked seven times in the first two games.

"We protected him better than we have," Denver coach Gary Kubiak said.

The Lions (0-3) are off to their worst start since 2010, when they finished 6-10.

"We do have 13 games left," Lions coach Jim Caldwell said. "They're not handing out trophies after three games and you can't be eliminated after three games."

Aqib Talib blocked an extra-point kick by former Bronco Matt Prater early in the second quarter to keep Denver's one-point lead. The Broncos also stopped a 2-point conversion run, keeping them ahead 14-12 early in the third quarter.

Stafford had three turnovers, including a fumble and interception at midfield in the fourth quarter. He might've had a good reason to be rattled because DeMarcus Ware sacked him twice and he was hit and hurried all night in Detroit's home opener.

"Anytime you have that many turnovers, that's going to give you some problems," Caldwell said.

Broncos running back C.J. Anderson left in the first half to be evaluated for a concussion, but was cleared and returned in the second half.

Both teams struggled to run the ball. The Broncos had more success through the air.

And, they took better care of the football.

Thomas had nine receptions for 92 yards and a lead-padding score in which he outleaped Darius Slay to snatch the football out of the air. He celebrated by backpedaling into the end zone, drawing an unsportsmanlike conduct penalty.

Stafford was 31 of 45 for 282 yards with a 16-yard TD pass to Ameer Abdullah in the third quarter, two interceptions and a fumble on a play in which he had at least once chance to throw the ball away. Calvin Johnson had eight receptions for 77 yards and drew a pass-interference penalty against Talib in the end zone to set up Joique Bell's 1-yard leap over a pile of lineman.

It looked as if Detroit's defense was going to prevent the Broncos from taking advantage of Stafford's second turnover, but it negated a missed field goal by being in an illegal formation. Denver got 5 yards closer and Brandon McManus made the field goal to give the Broncos a five-point lead.

The Lions had a chance to come back, but Stafford blew it. Stafford tried to force a pass to Johnson and safety David Burton Jr. dropped into a zone to pick off the pass that he tipped to himself with his right hand, then returned 12 yards.

"Our responsibility is get to the ball on defense," Burton said.

Moments later, Manning lofted a 34-yard pass to Emmanuel Sanders, who outjumped Slay, to set up his throw that only the 6-foot-3 Daniels could catch in the end zone.