In a multi-billion venue built for champions, the Los Angeles Rams have carried off the crown jewel: a Super Bowl trophy.

It took a precise 79-yard drive led by quarterback Matthew Stafford and capped by Cooper Kupp's 1-yard touchdown reception with one minute 25 seconds remaining for a 23-20 victory over the Cincinnati Bengals.

With the win, the Rams, whose only other NFL title came 22 years ago when they were based in St Louis, joined last year's Tampa Bay Buccaneers as the only teams to win a Super Bowl on their home field -- doing it in front of a sell-out crowd at the $A7 billion SoFi Stadium.

The winning drive, during which Kupp's 4-yard touchdown reception was negated by offsetting penalties, ended soon after with the NFL offensive player of the year easily beating Eli Apple in the right corner of the end zone for the winning score.

Star wide receiver Kupp had four receptions for 39 yards on the championship drive.

"Those guys just did a great job," Rams coach Sean McVay said. "They took over the game.

"So many contributions. It's about these players."

Even with that brilliant, decisive march to the Lombardi Trophy, it was LA's "fearsome fivesome" that made the difference.

Led by Aaron Donald and Von Miller, they sacked Joe Burrow a Super Bowl record-tying seven times, shutting down the Cincinnati offence after a 22-second spurt to start the second half gave the Bengals the lead.

Fittingly with time almost up, Burrow was under pressure from Donald on fourth-and-1 and threw an incomplete, setting off a football fiesta this city has not seen since the LA Raiders won the 1983 championship.

The 10 quick points at the outset of the third quarter put Cincinnati ahead for the first time.

Tee Higgins' 75-yard score made it 17-13 and was followed one play later by Chidobe Awuzie's pick.

Evan McPherson tied Adam Vinatieri's postseason record with his 14th field goal, a 38-yarder.

Higgins beat All-Pro cornerback Jalen Ramsey on the first play of the second half - the receiver clearly tugged Ramsey's face mask on the play.

After Matthew Stafford was intercepted on the next play, the Bengals got McPherson's field goal.

Then they tried to hold on as all of southwest Ohio held its breath.

But LA's relentless pass rush, led by its two biggest stars, Donald and Miller with two apiece, allowed nothing more.

Then came the decisive 15-play march, in which Kupp also converted a fourth down with a 7-yard run before his second touchdown of the game.

"It just comes down to this team and they way we prepared, they way we loved each other, trusted each other," Kupp said.

Kupp even earned the MVP honour despite often being double-teamed after fellow wideout Odell Beckham Jr went out with a knee injury in the second period.

Bengals head coach Zac Taylor said he was frustrated to lose knowing his team had an opportunity to tie or take the lead near the end.

"We were moving the ball. We were going to try to go win it," Taylor said.

"(To work) for the last six months, play 21 games, then you lose the Super Bowl - it's not a lot of fun."