Brought in to stabilize the position, he instead struggled behind a shaky offensive line, often times turning the ball over while failing to deliver big plays.
Whether Palmer's status as the team's starter was ever in doubt we will never know, but there was some thought that continued struggles against the Atlanta Falcons could lead head coach Bruce Arians to make a change.
Palmer threw an early interception in that game, but ended up completing 13-of-18 passes for 172 yards and two touchdowns. Then, following the bye week, Palmer rebounded from another early pick to finish 20-of-32 for 241 yards and two scores against the Houston Texans.
His QB rating over the two games is a sterling 101.5 (compared to 69.45 in the first seven games), and if nothing else, it appears the team may be capable of performing at a high enough level with the veteran under center.
"Carson did a great job for us today," receiver Larry Fitzgerald said after Sunday's 27-24 win over the Texans. "He made some great throws."
Fitzgerald added that Palmer did a good job finding multiple targets and made a lot of difficult throws with pressure around him.
"Carson did a great job of leading us to a win."
Granted, it would be wrong to attribute the win solely to the QB's play. As usual, the defense deserves the bulk of the credit, and without the unit's continued excellence the Cardinals would not be sitting at 5-4 with a shot at the playoffs.
However, the team's first seven games proved that even a great defense could not lead the team to wins without some semblance of a productive offense. Aided by an effective running game, Palmer has been able to provide just that.
"We are a tough, grind it out, defensive team," Palmer said after Sunday's win. "I think that is our M.O. We keep believing. We won a lot of games in the fourth quarter and hung around long enough to find ways to win games.
"I think that has been our mindset. I don't know what everyone else thinks, but that is what we have been thinking in our locker room."
If nothing else, Palmer's performance over the last two games likely served to quiet those calling for backup Drew Stanton to take over. For the season, Palmer has completed 194-of-316 passes, for 2,154 yards with 12 touchdowns and 15 interceptions. He ranks 15th in the NFL in yards and completion percentage, and his touchdown total puts him in a tie for 17th.
He hasn't been great by any means, but he has been good enough and appears to be getting better.
"He's just like the rest of us," guard Daryn Colledge said Sunday. "He's been here one year or 20 weeks now since camp. He's out there still trying to mesh with us. He's trying to get his stuff figured out.
"The great thing about Carson is he's a true professional; he's not going to be happy with the way he played today. He could have thrown for 400 yards and he still wouldn't have been happy with the way he played."
Maybe not, but if Palmer continues to play like he has the last two games, most people will be.