Doornbos joins Newman/Haas/Lanigan

The Dutchman raced in F1 for Minardi and Red Bull in 2005 and 2006, before moving to the Champ Car World Series with Minardi USA the following year.

He was immediately a front-runner in America, winning twice and taking third in the championship at the first attempt, but he was unable to find a drive when Champ Car and IndyCar merged last year, so instead raced in A1GP and the Superleague Formula.

"I'm very happy and proud to get this chance to race with Newman/Haas/Lanigan Racing," Doornbos said.

"Racing in the IndyCar Series has been my biggest dream and especially to do it with Newman/Haas/Lanigan Racing. The history of the team and the big success they have had in the past really attracted me, and it makes me proud to become part of this winning team."

By the time Doornbos reached Champ Car, the series has dispensed with all its oval dates, so his first taste of oval driving will come in next week's Homestead test.

"Racing on the ovals should be very exciting," said the 27-year-old. "It will be tough, but I'm training as much as possible and am in good condition and ready to achieve results. I'm also excited to race in the legendary Indy 500.

"I really want to thank Mr Haas and Mr Lanigan for giving me this chance. I'm looking forward to the first race."

Doornbos had been linked with Newman/Haas/Lanigan for much of the winter, but it took until now to finalise his deal with the team, who had been struggling for sponsorship and had to release their 2008 driver Justin Wilson. The sponsor package for Doornbos's car has yet to be announced.

Team co-owner Carl Haas said he rated Doornbos highly after he pushed then-Newman/Haas/Lanigan driver Sebastien Bourdais hard in 2007.

"He was a fierce competitor in Champ Car, and we are hoping for the same in the IndyCar Series," said Haas.

"He was able to quickly adapt to the new challenges in Champ Car, which should bode well for the learning curve we will face in getting him acclimatised to oval racing."

Graham Rahal has already been signed for Newman/Haas/Lanigan's second car, and reports in America have also linked Milka Duno to a third entry from the team.