Herta to sub for Nakano

Herta is contracted to Forsythe Championship Racing, but a political dispute between Forsythe and the sport's governing body led to the team withdrawing - though it may appear later in the season.

Nakano made a promising CART debut at Homestead, but crashed heavily in a test at Milwaukee. Afterwards, the Japanese driver complained of headaches and dizziness, and was found to have slight haemorraging in his brain.

It was believed that Memo Gidley would sub for Walker, but CART's official website has reported that the driver for the Long Beach and Rio events would be the sidelined Herta.

"After missing the first couple of races of the 2000 season, I was definitely itching to get back in the car," said Herta.

"When Derrick presented me with this opportunity, it was a good chance for me to do some competitive racing while giving the Forsythe team some time to sort out their situation.

"I'm grateful to Derrick and Gerry for allowing me this opportunity."

Walker was similarly pleased with his new charge, who has won two CART races in his career.

"Bryan is a winner and was a natural choice to use as a substitute driver for Shinji, "said Walker. "We were very fortunate to be able to find a driver of his calibre who was also available. We owe Forsythe Racing and Gerry Forsythe."

Nakano is reported to be making good progress, and should be racing again in two to three events' time.