Ryan Hunter-Reay storms to victory at the Iowa Corn Indy 300

With eight laps left, Hunter-Reay was 10th but powered through the field, having taken on fresh tires, to eventually overtake Tony Kanaan on the penultimate lap and win.

It was Hunter-Reay's first win since the Indianapolis 500 in May and it was enough for the 33-year-old from Andretti Autosport to move into third overall with 439 points.

Josef Newgarden (Sarah Fisher Hartman) finished second, overhauling Kanaan (Target Chip Ganassi) on the last lap.

Kanaan had to settle for third, while his team-mate and reigning IndyCar champion Scott Dixon finished fourth ahead of Ed Carpenter.

Helio Castroneves finished eighth to claim first spot in the overall standings with 471 points, leapfrogging fellow Team Penske driver Will Power (462).

Hunter-Reay is third ahead of Schmidt Peterson Motorsports' Simon Pagenaud (421) and Team Penske's Juan Pablo Montoya (405).