Conversation so far:
What happened to Kurt Warner in the 2009 season?
Kurt Warner announced his desire to return to the Cardinals for the 2009 season.
Why did Kurt Warner want to return?
The Cardinals offered him a two-year contract worth around $20 million but Warner was looking for a contract that would pay him about $14 million a year.
Did Kurt Warner get the contract for $14 million a year?
The Cardinals and Kurt Warner could not come to an agreement.
How did Kurt Warner perform that 2009 season?
On September 20, 2009, Warner broke the NFL's single-game record for completion percentage in the regular season, completing 24 of 26 passing for 243 yards and two touchdowns.

Question: What was the record?
Self-contained rewrite: What was the record that Kurt Warner broke in the 2009 season?