Sergio Perez has completely recovered from the virus which hit the Force India driver in Malaysia last week and almost kept him from racing.
His fitness weakened by the sudden infection, Perez struggled to reach the checkered flag in Sepang but pressed on to achieve an impressive sixth-place finish.
"I think I’m 100 percent for this weekend," Perez said.
"I got a big virus infection and that hit me quite hard and then to recover took me quite a while. On Monday I was already feeling a lot better.
"Sunday was my hardest race I’ve done physically. It was so tough. Muscularly, it was like I had no strength at all and really, really struggled.
"I was quite lucky actually I had such an easy race. In general to hang in there was quite difficult."
The Mexican had his doubts early on in Malaysia about his ability to drive, but fueled by his determination he pulled himself up and went to work.
"There was a point in the weekend, probably on the Thursday, early Friday without the limited running I thought probably I’m not going to be able to do the weekend given my condition," he said.
"Progressively it got better. The weather helped me, we didn’t run too much on Friday. I got away with it and I was lucky to be able to get away from that one."
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