After the prolonged 'will he, won't he' hype surrounding his move to the IndyCar Series, Robert Doornbos has called time on his deal with Newman/Haas/Lanigan Racing, despite being in contention for rookie of the year honours.

The Dutchman sits a point ahead of main rival Rafael Matos following last weekend's Kentucky round, but is poised to quit the ultra-successful NHLR operation with immediate effect.

The Indianapolis Star newspaper reports that Doornbos has confirmed the split, and intends to pursue another ride within the series, most likely with HVM Racing. Keith Wiggins team ran the Dutchman in the 2007 Champ Car series, leading to a brace of victories, but could not reach a deal to bring him back for 2008, and then saw the sometime F1 driver opt for NHLR in 2009. However, despite the team's pedigree, and his position in the rookie standings, Doornbos has struggled this season, with a best of ninth place, which he achieved three times in twelve races.

Although no official announcement has been received, Doornbos is expected to take his family-funded programme to HVM, possibly in time for this weekend's Mid-Ohio road course round, where he will form a two-car line-up alongside EJ Viso. It remains to be seen whether NHLR will replace Doornbos or decide to run a single-car operation for Graham Rahal, although a certain Sebastien Bourdais is currently on the market, having been dropped by the Scuderia Toro Rosso F1 team. The Frenchman contributed hugely to NHLR's previous success, claiming the final four Champ Car titles prior to unification with the IndyCar Series.

HVM has the capability to run two cars, having fielded Nelson Philippe alongside Viso at Indianapolis, and the Doornbos story comes just as the Frenchman reveals that he will return to the IRL with Conquest Racing.

Running the same I Drive Green campaign as he took to the Brickyard, the 23-year old will contest the Infineon Raceway and Homestead-Miami Speedway rounds with Eric Bachelart's team, which recently announced that it would also make the trip to Motegi to run Kosuke Matsuura.

Like Doornbos and HVM, Philippe will be making a return to a former team, having piloted a Conquest car in six Champ Car races in 2004 and a full season in 2005, before returning for the final two races of the 2007 campaign.

“We've always maintained an excellent relationship with Nelson and we're very happy to have him back with us once again,” Bachelart commented, “We first had Nelson with us when he was an 18-year old rookie, and it's been nice to see him mature into the race car driver he is today. He had his first taste of the Dallara back in May on the Indianapolis Motor Speedway and we look forward to seeing him back in an IndyCar at Infineon Raceway and Homestead-Miami Speedway.

“We're also excited to be promoting and partnered with such an innovative and interesting project as the I Drive Green programme, and are looking forward to working with Nelson to go racing full-time in 2010.”