Giorgio Pantano becomes the latest driver to stand in for the injured Justin Wilson

While Dreyer & Reinbold regular Wilson recovers from a broken back sustained in practice for the Mid-Ohio event earlier this month, the team has opted to fill his seat with the vastly experienced 32-year-old Italian - who last raced an IndyCar in 2005.

Team co-owner Dennis Reinbold said: "We are extremely excited about putting Giorgio in our car at Sonoma and Baltimore.

"He will add another dimension to our programme and we are happy to have him on board for those events," Reinbold added. "We will be testing him at Sonoma this weekend and we are excited to get him acclimated to the car. Giorgio has a lot of experience and talent and we believe he will be a good fit."

Pantano competed in two IndyCar races for Chip Ganassi's squad in 2005, again at Sears Point and also Watkins Glen - where he finished fourth.

Since then Pantano has completed four seasons of GP2 - winning the championship in 2008, before switching to Superleague in 2009 after failing to secure a return to F1 on the back of his title.

The Italian then did a season in AutoGP last year with a best finish of third at Spa.

"For me, this is a very good opportunity," said Pantano. "I want to say thank you to Dreyer & Reinbold Racing and the sponsors for giving me this opportunity. I'm here to do the best that I can as always and I look forward to the chance to compete in these two races."

Since Wilson's injury at Mid-Ohio, D&R have so far called upon the services of Simon Paganeud and Tomas Scheckter to stand in.

The team remains undecided on its line-up for the final roadcourse event at Motegi and the last two races of the season, both on ovals at Kentucky and Las Vegas, though Wilson has stated his target is to return for the season finale.