Sean McVay "loved everything" Matthew Stafford did in his spectacular debut for the Los Angeles Rams as he led them to a 34-14 win over the Chicago Bears.

In the first regular-season game with fans at SoFi Stadium, Stafford delighted a packed house with a display of why the Rams traded two first-round picks to acquire him from the Detroit Lions.

Stafford completed 20 of 26 passes for 321 yards and three touchdowns, posting a passer rating of 156.1, the highest ever by a player in his debut with a new team. 

And McVay could hardly have been more effusive in his praise of his new quarterback.

"I think it was just his steady demeanour throughout the course of the game," McVay said. "Just like you had seen in practice and seen from afar, but I think the first drive of the second half I thought was most impressive.

"But then I'm thinking about what an unbelievable job he did progressing, finding Robert Woods on the last touchdown, so there were multiple things but I think the overall game management and I think the expectation. You could just see there was a look in his eye. He had confidence in his team-mates.

"He expected to play well and he did a great job. It's hard to say there was one thing. I loved everything he did tonight."

Stafford's second throw of the game saw him hit Van Jefferson on a 67-yard touchdown throw on which he booted to his left off the play-fake, flipped his hips back to the right sideline and unfurled a perfect ball to find the second-year receiver on a deep post route.

"I think it was a great job by him being able to flip his hips and make an unbelievable throw," McVay added.

"I think that's kind of one of those things – he's gifted. He's got a great ability to be able to change his arm slot and make all types of throws, whether it be short, intermediate or down the field.

"You're not limited in anything you can do in the pass game. Hopefully, we'll continue to build on options and opportunities that we have moving forward."