The Rams have nine new draft picks joining the roster, plus a handful of free agents like wide receiver DeSean Jackson. But Stafford is the acquisition that will face the most public scrutiny.
The Rams traded Jared Goff and several draft picks to the Detroit Lions in exchange for Stafford earlier this year.
The 12-year NFL veteran has always been highly regarded for his passing skill at the position but met with limited success in Detroit.
Rams fans and experts have high hopes for the combination of Stafford with Sean McVay, entering his fifth season as head coach. An ESPN poll of league officials and players projected Stafford as the league's No. 6 quarterback for the 2021 season.
Stafford said he still has plenty to learn about McVay's offensive schemes, but said he was glad the trade happened early in the year, giving him time in the spring to start studying.
"I definitely have a lot to learn," Stafford said. "And still can continue to get better within the offense. That's everybody in this league. The second you think you got it all figured out, it's not that way."
The Rams open the season hosting the Chicago Bears at SoFi Stadium on Sept. 12.
Rams open 2021 season against Chicago Bears