Sorgi completed 7 of 12 possessions for 67 yards. But rookie Matt Ryan and journeyman Chris Redman left the Falcons wondering who will run the team's offense this year.
Ryan, who was the NFL's No. 3 overall draft pick, threw an interception shortly after entering in the second quarter. Kevin Hayden returned it for a 67-yard Colts touchdown.
That gave the Colts a 10-6 lead that they would maintain the rest of the game, despite a third-quarter field goal from the Falcons' Jason Elam.
But backup kicker Adam Crossert sealed Indy's victory with a field goal in the third and another late in the fourth.
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