The Chilean was forced to be content with a place on the bench for the 2-0 loss to Slaven Bilic's side, featuring for just the final 23 minutes.
Meanwhile, Mathieu Debuchy filled in at right-back due to the Spaniard's knock but both could start at Selhurst Park on Sunday.
"Alexis Sanchez is fit, he's been working hard and is ready for the weekend," Wenger told the club's official website.
"Hector Bellerin is back and is available for Sunday."
However, Wenger will be without the services of Danny Welbeck and Tomas Rosicky for the foreseeable future, but said the England forward was getting closer to a comeback.
"Welbeck is making good progress but is still not available.
"Tomas has had surgery on his knee. His agent said he will be out for one or two months but it will be longer. How long exactly, we don't know yet."
Finally, Jack Wilshere, who has a cracked fibula, is still set to recover on schedule.
"We said Jack would be out for four weeks, and he's in the second week now so he's on schedule."
