Kolb then made two starts before a concussion suffered during an inadvertent collision ended his season.
2011-2012 Kolb: Weeks 1-5
Those injuries renewed questions about Kolb's durability. A concussion suffered during the 2010 opener, when Kolb was with Philadelphia, had opened the door for Michael Vick to become the Eagles' starter.
Kolb's ability to withstand 17 sacks over the Cardinals' past two games has put to rest, for now, those durability questions.
Now we can focus on things such as how well Kolb is playing. My impression is that Kolb has shown improvement from last season. He has thrown fewer interceptions. He has led game-winning drives.
Kolb has also done these things without much help from the Cardinals' ground game. Arizona has struggled to run the ball for obvious reasons. Injuries on the line have had some impact. Losing two of the top three running backs for multiple games has surely hurt in that area.
In looking at the stats, Kolb doesn't appear much more productive than he was through five games last season.
I would have said he appears more willing to stand in the pocket and play within the framework of the offense, but the stats don't back up that impression.
Kolb has left the pocket 27 times and remained inside it 160 times. Last season at this point, the ratio was 31 plays outside the pocket and 169 within it. Those numbers, provided by ESPN Stats & Information, suggest no fundamental change.
Once outside the pocket, Kolb has completed 54.5 percent of his passes for seven first downs. That's an improvement from this point last season, when Kolb had completed only 33.3 percent of passes with six first downs when straying from the pocket.
The chart includes a "QB PAR" line showing how many points Kolb has accounted for above a replacement-level quarterback, based on the metrics ESPN uses to calculate Total QBR.
Those metrics show Atlanta's Matt Ryan leading the NFL at plus-33.4 PAR, followed by Peyton Manning (32.0), Tom Brady (30.7) and Andrew Luck (29.2). Alex Smith is at 21.5, which ranks 16th in the NFL, one spot above Drew Brees. Kolb ranks 25th, between Tony Romo and Blaine Gabbert. Sam Bradford is 28th at 8.0. Russell Wilson is 31st (3.2). Brandon Weeden is the only player in the negative (minus-16.1).
Kolb's NFL passer rating is higher this season than it was through five games in 2011. His QBR score, which takes into account how passing and non-passing contributions affect a team's chances for winning, is about the same.
The takeaway for me: The Cardinals' poor ground game and diminished pass protection have made Kolb's life tougher. The team's vastly improved defense has made his life easier, allowing Arizona to win some games without asking as much from him. The positive late-game plays Kolb has made should be encouraging for the Cardinals. But the team's 4-1 record shouldn't lead us into blindly accepting the idea that Kolb is playing dramatically better this year. He might not be.