The number one and two seeds, who both finished their seasons with 13-3 records, faced off in the NFC Championship game and it was the Saints who made most of the early running.
Kicker Wil Lutz was true with the boot from 37 and 29 yards and quarterback Drew Brees found Garrett Griffin for a five-yard touchdown as the Saints led 13-0 after the first quarter.
The Rams bounced back in the second, Zuerlein making a field goal from 36 yards and Todd Gurley rushing from six yards to reduce the deficit to 13-10 at the half.
Brees – 26 of 38 for 249 yards – got his second touchdown of the day in the third, passing two yards to Taysom Hill, while the Rams QB Jared Goff got his first score to Tyler Higbee as the sides entered the final 15 minutes at 20-17.
A 39-yard pass from Goff to Gerald Everett gave the Rams decent field position late in the fourth, but Los Angeles had to settle for a field goal to tie the game at 20-20.
Lutz made his third field goal of the night as the Saints took a slender lead, but Zuerlein was good from 48 yards with 20 seconds left as the game went into overtime.
Brees was intercepted for the first time in overtime as John Johnson got the pick at the 46-yard line to give the Rams good field position.
The drive stalled as Zuerlein was, once again, called into action for a 57-yard field goal attempt.
The 31-year-old split the uprights as the Rams booked their ticket to the Super Bowl, 20 years since the Rams – then based in St Louis – beat the Tennessee Titans in Super Bowl XXXIV.