Two normally trustworthy kickers misfired and the end result was the NFL's first tie in nearly four years.
David Akers and Greg Zuerlein both missed field goals in overtime and the San Francisco 49ers and the St. Louis Rams played to a 24-24 tie.
It was the NFL's first tie since Nov. 16, 2008 when the Philadelphia Eagles and Cincinnati Bengals finished their contest knotted at 13-13.
Akers, who sent the game into overtime with a 33-yard field goal with three seconds remaining in regulation, sailed his kick wide left from 41 yards out midway through the extra session.
Zuerlein initially nailed a 53-yard attempt on St. Louis' ensuing series, but a delay of game penalty was called. The rookie kicker, who split the uprights from 60 yards away earlier in the year, missed to the right from 58 yards out.
Alex Smith was 7-of-8 for 72 yards and a touchdown before exiting the contest with a concussion.
"He had blurred vision," 49ers head coach Jim Harbaugh said of Smith.
Smith suffered the concussion late in the first quarter on a quarterback scramble. As he began to slide, he turned his back to linebacker Jo-Lonn Dunbar, who hit Smith around the neck area. Smith stayed in the game temporarily before leaving in the second quarter.
Colin Kaepernick came on and threw for 117 yards on 11-of-17 efficiency and added 66 yards on the ground for San Francisco (6-2-1), which had won four of its previous four games coming in.
"The way I feel it was a good football game, it was a hard fought game, it came out even," Harbaugh said.
Frank Gore carried the ball 21 times for 97 yards and a score, while Michael Crabtree caught five passes for 70 yards and a touchdown in the tie.
Danny Amendola, who was supposed to miss 6-to-7 weeks with a collarbone injury, returned after just a three-game absence and had 11 receptions for 102 yards for the Rams (3-5-1), who snapped a three-game losing streak.
"I have to say, I've been doing this a while. I don't think I've ever been in a game like this," Rams head coach Jeff Fisher said. "We had a number of chances to put the game away. And, unfortunately, we didn't."
Sam Bradford completed 26-of-39 passes for 275 yards and two scores, while Steven Jackson ran for 101 yards and a touchdown on 29 rush attempts in the tie.
"It's a weird feeling. I've never been a part of a game like that before," Bradford said of the tie.
On the first play of overtime, Bradford lofted a perfect pass to Amendola, who outran 49ers cornerback Carlos Rogers on an out-and-up route, for an 80-yard completion down the San Francisco 2.
The huge gain was negated, though, due to an illegal formation penalty. The Rams were forced to punt four plays later.
After both kickers missed their field goals, the 49ers went three-and-out and St. Louis regained possession at its own 14 with 1:36 left.
The Rams, however, were unable to move the ball past midfield before time expired.
Zuerlein nailed a 27-yard field goal with 27 seconds left in the third quarter, which gave the visitors a 17-7 lead.
San Francisco, though, responded with 14 points over just a 17-second span midway through the fourth.
Out of the pistol formation, Kaepernick broke free along the right edge on a bootleg, turned the corner and dove for the score to cap the 11-play, 81-yard march.
After Isaiah Pead fumbled on the ensuing kickoff, Gore ran it in from 20 yards out one play later to make it 21-17 with 8:23 to play in the frame.
Bradford flipped a 2-yard TD pass to Austin Pettis, which concluded an elongated 14-play 81-yard, 7:14-trek, on the Rams' next touch and gave the Rams a 24-21 advantage with 1:09 to go.
Earlier, the Rams scored touchdowns on their first two possessions of the contest and jumped out to a 14-0 lead.
Bradford found Brian Quick for a 36-yard score on St. Louis' initial drive and Jackson ran it in from seven yards out late in the opening period.
Smith hit Crabtree for a 14-yard score midway through the second, which cut the margin to 14-7.
St. Louis hasn't won in San Francisco since 2007 ... The Rams were 7-of-16 on third down, while the 49ers finished 2-of-11 ... St. Louis outgained San Francisco, 458-341.