Dario Franchitti led most of the IndyCar Series race in Iowa on Saturday night, but a slow late pitstop dropped the Scot down the order and opened the door to an impressive win for Marco Andretti. The 24-year-old has struggled in recent years and again this season as one of four drivers in father Michael’s Andretti Autosport’s team. In fact, Marco had not won a race in 79 starts, since his first IndyCar victory at California’s Sears Point road course in 2006 – his rookie season.

Tony Kanaan chases Iowa winner Marco Andretti

So it was good to see Andretti score a deserving win on the 7/8ths-mile Iowa oval as he chased Franchitti through the middle of the race and battled back and forth with Tony Kanaan in the closing stages. Andretti clung resolutely to his lead over the last 19 laps despite Kanaan’s best efforts. “Knowing TK,” said Marco, “I knew he would do exactly what I did to him. He’d make his car very wide. I didn’t want to wait until two [laps] to go because he was just going to chop me and I would have been done. I knew I had to get it done earlier and make my car wide.”

Andretti was by far the most competitive of his father’s four cars in Iowa with Ryan Hunter-Reay finishing eighth, Danica Patrick 10th and Mike Conway taken out by Ana Beatriz in an early accident. Kanaan enjoyed another competitive race, and plainly his presence at KV Racing this year has helped push the team to new heights. Kanaan qualified third in Iowa while team-mate Takuma Sato took pole position and led the opening laps. Sato became the first Japanese driver to take an IndyCar pole and ran well in the race until losing control and crashing on the Iowa track’s notorious Turn 2 bump.

Dario Franchitti congratulates Michael Andretti on his son’s win

Championship leader Franchitti set the pace through the first two-thirds of the race but came out of the pits from his second stop behind Andretti. In traffic Dario’s car wasn’t as good as in clean air and he slipped back as the car got more and more tail-happy. He finished fifth but continues to lead the championship after Will Power crashed in Iowa. Franchitti’s Ganassi team-mate Scott Dixon drove well, coming through the field to finish third after qualifying a disappointing 23rd.

Power qualified fifth but damaged his car in a collision in the pits with Charlie Kimball. Later in the race the Team Penske driver crashed, losing valuable ground to Franchitti in the title chase. After eight of 17 races Franchitti leads with 303 points to Power’s 283. Dixon is third with 230 points followed by Oriol Servia (214) and Kanaan (211).

Polesitter Takuma Sato is pursued by team-mate Kanaan

Iowa was the last of three consecutive weekends of racing on oval tracks for IndyCar. The series has next weekend off before a pair of Canadian races in July at a street track in downtown Toronto and an airport circuit in Edmonton. It will be interesting to see if Power and Team Penske can put any pressure on Franchitti and Chip Ganassi’s team, and whether the likes of Andretti, Kanaan, Dixon or Servia can pull themselves into the championship hunt.