Yet when Palmer was asked on Wednesday if he remembered what happened the last time that he faced St. Louis, the quarterback had a playful response, saying "What happened last time?"
There is no doubt that the 13-year veteran is trying to move on from the second ACL tear of his NFL career, and according to NFL Media's Alex Flanagan, the quarterback is focused on the task at hand in Week 4.
"What happened last year, happened last year," Palmer said.
This year the Rams have one of the NFL's most stout defenses. The team is tied for the NFL lead with 13 sacks and boasts arguably the best defensive line in football.
St. Louis will have a great challenge on its hands, too. Arizona leads the league with the most points per game (42) heading into the game.
The difference between the two teams is Arizona has a defense that can go toe-to-toe with anybody -- and the Rams' offense doesn't scare anybody. And with Palmer back healthy, the team looks primed for a deep postseason run.
"We are confident because we are good and we know it," Palmer said.