Justin Allgaier had taken the top spot for the green flag, leaving Sam Hornish Jr. and Michael McDowell fighting over second spot ahead of Jason Leffler and Cole Whitt. Further back, Danica Patrick and Kurt Busch were battling over ninth place; Busch was one of four drivers (along with Hornish, Mike Bliss and Joe Nemechek) to have flown in from Sprint Cup Series duties at Pocono in time to do a double shift in Iowa.
By the time the race reached half distance, Allgaier's lead was an impressive two seconds over Elliott Sadler who had calmly worked his way back up to second ahead of Hornish, Dillon and Michael McDowell. McDowell made light contact with a lapped car down the backstretch and lost a couple of positions, while Dillon came to pit road very early on lap 138 complaining of a serious vibration.
The rest of the field weren't expecting to pit until around lap 180m but before that could materialise there was a debris caution on lap 172 to make the visit to pit road more amendable. Allgaier and Sadler remained in charge of the front row for the subsequent restart, with Kurt Busch, Ricky Stenhouse Jr. and Sam Hornish Jr. making up the rest of the top five.
Allgaier was once again unbeatable at the restart and blasted away, but Sadler was safe enough in second place and the comparatively old hand bided his time, started to make in roads into Allgaier's impressive lead, and then - when he judged the moment to be right - he made his move. On lap 192, Sadler dived under the inside of the #31 and emerged from turn 1 with the lead of the race for the first time in over a hundred laps.
"When I got to Justin, I had a hard time passing him," said Sadler."He kind of knew where my car was fast. He made one slip off turn four and opened the door for me. I got a really good bite under him. I knew once I got out front we were in really good shape."
Not that Allgaier was about to let Sadler walk off with the race after having led 101 laps of the race. Anytime Sadler threatened to break way, Allgaier would put his foot down and close right back up to the the #2 and it was impossible to tell which of them truly had the upper hand for the closing stint of the race.
A caution could have changed the entire complexion of the race, but none appeared> Austin Dillon's spotter made the case for debris on lap 206 when his man was in the lucky dog position, but that came to nothing. Nor did Danica Patrick's slide up the race track into a light brush against the wall in turn 4 a couple of laps later while running in tenth place, costing her a few positions in the process. By this point, only 15 cars were on the lead lap - and that was reduced by one more near the end when Kurt Busch pitted on lap 244 with a shredded right tyre and a small fire in the wheel well, having complained of high temperatures for much of this final stint. He'd been running in third when the tyre let go, and ended up finishing in 17th as a result.
The longer the run went uninterrupted, the happier Sadler was looking out on front and the less likely it seemed that Allgaier was holding anything back for a last minute challenge. The gap between first and second remained steady at around a second, and while a final half-hearted charge from Allgaier cut that to 0.649s he could do nothing more about preventing Sadler from claiming the chequered flag.
"It's tough to see Elliott out there and know you're catching him and there's not really much you can do," admitted Allgaier after the race ended. But he didn't appear too downhearted: "To come here and lead the most laps and run as good as we did, I was proud of that."
Sadler was delighted with the win, although clearly the issue last week at Indianapolis was still playing on his mind. "This would be three wins in a row for my race team" if not for last week's penalty, he said.