Updated

The Carolina Panthers' close losses are becoming more and more painful.

In the latest, they gave up a last-second touchdown to the Buffalo Bills in a 24-23 defeat Sunday.

"This is like going to the dentist and getting several teeth pulled without any anesthesia, laughing gas, nothing," said Panthers receiver Steve Smith. "It's tough and it's sickening."

The Panthers failed on multiple opportunities to close out the Bills and rookie quarterback EJ Manuel despite forcing two fourth-quarter turnovers by Buffalo. Carolina had to settle for field goals from Graham Gano both times.

Manuel then led a nine-play, 80-yard drive in 96 seconds, finding Stevie Johnson in the left corner of the end zone for a 2-yard touchdown pass with 2 seconds left.

The Panthers fell to 2-14 in games decided by 7 points or less under coach Ron Rivera.

"We had an opportunity to win the game and close it out and we couldn't do it," said Rivera. "That's the bottom line. We had a chance to make plays, and we didn't."

The Panthers opened the season with a 12-7 loss to Seattle during which they squandered a 7-6 fourth-quarter lead.

Injuries to their already-thin secondary also played a role against Buffalo.

Carolina lost cornerback Josh Thomas to a concussion in the first half and safety Charles Godfrey to a right Achilles tendon injury in the second. Reserve defensive backs Josh Norman and Quintin Mikell were also slowed by injuries during the game.

"Everything that could've gone wrong did," Carolina linebacker Thomas Davis said.

The Panthers opened up a 23-17 lead thanks to some strong plays by Cam Newton, who finished 21 of 38 for 229 yards, two touchdowns and an interception. But he couldn't turn two Bills turnovers deep in Buffalo territory into touchdowns.

"Our efficiency in the red zone has to be better, starting with me," Newton said.

Newton threw a 40-yard touchdown to Ted Ginn Jr. on Carolina's first drive of the second half, but the Panthers' deep game otherwise struggled.

"We were just this far off with shots down the field," Newton said. "We thought we'd give our guys an opportunity, Steve, Ted, those guys."

It was the first victory for the new-look Bills under Manuel and coach Doug Marrone. The win came on a day when the Bills honored their 28-member Wall of Fame — a group that includes Hall of Famers Jim Kelly, Thurman Thomas and Marv Levy — during a halftime ceremony, and a week after the Bills squandered a last-second lead in a 23-21 season-opening loss to the New England Patriots.

Manuel became the fifth NFL rookie since 1960 to engineer a fourth-quarter comeback in his first or second game.

Bills defensive end Mario Williams set a team record with 4½ sacks.

The Panthers' usually stout defense had an unlikely second-half meltdown. The Bills had four scoring drives on six possessions — and also scored on a 2-point conversion when Manuel hit rookie receiver Robert Woods.

It was another lead the Panthers couldn't hold.

"I'm not going to finger point or any of that," Smith said. "I just know that overall, our result was a loss."