Will Power on medication ahead of return to IndyCar testing

The Penske driver was forced to sit out Sunday's race after tests suggested he had suffered a concussion in an accident during free practice.

While Power was potentially too unwell to drive anyway, reporting sickness and headaches while also recovering from an inner ear infection, IndyCar doctors now believe the latter was a result of muscle tension.

Former CART doctor Steve Olvey, who took part in the testing process, said: "We were aware of his ear infection, which had been adequately treated and was much improved, but we also found that he had pretty marked cervical muscle tension.

"This can cause a pretty debilitating type of headache.

"It's usually bi-frontal, goes down the back of your neck, and you get into a vicious cycle with this unless you break it.

"So he is on some medication to relax the muscles of his neck and get the cycle broken."

Power missed a scheduled test outing at Barber on Tuesday, but he plans to make up for that early next week.

Olvey added: "If he steps back into the car the whole thing may repeat itself as far as his neck spasm goes.

"So we'd like him to sit out this week, but it's related to the cervical muscle problem, not a concussion.

"He should be able to get back in the car on Tuesday and have no further problem."

Power, who was replaced by Oriol Servia at short notice last weekend, said he felt clear of the symptoms he was suffering before the race.

"My inner ear is feeling better - I don't have headaches or nausea," he said.

"I'll be testing Barber next week to make up for the test - that will be good.

"Obviously it's great to be cleared to get back in the car again, that's the best medicine you can have."