Toyota test and reserve drive Mike Conway will make his LMP1 debut with the Japanese manufacturer at the Austin World Endurance Championship round next month.
The IndyCar race winner will drive the #7 Toyota TS040 HYBRID in the US event on September 20 in place of Kazuki Nakajima, who has a conflict with his Super Formula programme with the TOM'S team in Japan.
Conway won the LMP2 class in the WEC fixture at the US track last year.
"I'm really pleased to be given the chance to race a TS040 HYBRID," he said.
"It should be great fun to race at the front in Austin. I'm ready for this challenge and looking forward to showing what I can do."
Conway, who will drive alongside Alex Wurz and Stephane Sarrazin, gained experience of the TS040 in winter testing.
He drove the car at the Aragon circuit in Spain in March and is scheduled to drive again this month at an unspecified venue.
Nakajima will return to the Toyota line-up for round five at his home race of Fuji in October.
Conway is also contesting all the IndyCar road and street course rounds for Ed Carpenter Racing this year and will compete in Formula E for the Dragon team.
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