Former Wimbledon champion John McEnroe has heaped praise on South African Kevin Anderson for improving his game this year.
The 14th seed won the first two sets against defending champion Novak Djokovic in their fourth-round tie, but the Serbian hit back to take it into a decider, which will be completed today.
McEnroe told BBC Sport: "I have seen Kevin Anderson's groundstrokes before and I know how fit he is - I don't think there is a harder worker on the men's tour.
"But what really impressed me against Djokovic were his skills at the net. I have not really seen that before, but he showed what he can do with the way he took his set-point for the second set, it was beautiful drop volley."
The winner of the match will play Marin Cilic in the last eight.