Rafael Nadal fought through injury to come from behind to beat Taylor Fritz and reach the Wimbledon semi-finals.

The Spaniard, who had a medical timeout at the end of the second set and struggled with his movement for long spells, won 3-6 7-5 3-6 7-5 7-6 (10-4).

It keeps Nadal's bid for a calendar Grand Slam on track and sets up a semi-final against Nick Kyrgios.

Nadal, who had strapping on his abdomen in his previous match, seemed to be bothered by the same issue again.

The first question he faced after the forehand winner that sealed victory, in a match that at one point he looked like he might not be able to finish, was 'how did you do that?'

It was the one on anyone's lips who witnessed the events on an enthralled Centre Court.

"I don't know," the 36-year-old said.

Nadal, who was in sublime form in his previous two matches, had got off to a good start with a break in the opening game but Fritz raced to the net to launch a stunning forehand down the line to break back for 3-3.

From then on Nadal seemed troubled physically and when he handed Fritz a break with a double fault, the American wasted no time serving out the set with three aces in a row.

The Spanish 22-time Grand Slam champion went off court for treatment at 3-4 in the second set and although he returned to take that set, his movement continued to be hampered and he struggled on his backhand side and on his serve, which increasingly dropped in speed.

Hanging his head while sitting at the changeovers, Nadal looked lost, calling on the trainer at the end of a third set that he handed to Fritz when he sent a forehand wide. He had a chat with the trainer but no treatment, merely shaking his head before heading over to the baseline.

Nadal was broken eight times in the match, his serve frequently 25mph slower than that of his opponent, but he held it to love to take the fourth set and force a decider that had looked so unlikely at times.

This was a reminder that this is one of his sport's all-time greats and whose fighting spirit is his trademark.

Nadal had break points at 3-3 in the fifth, one of which was saved by a cruel net cord, before he finally converted the fourth with a delicate forehand drop shot.

But Fritz, who had beaten Nadal earlier this year in the Indian Wells final, responded brilliantly with an immediate break back and hold to leave the Spaniard serving to stay in the match as the clocked ticked past four hours.

He held firm and Fritz quickly held his own serve again with an ace, with Nadal then roaring when he took it into the tie-break, where he quickly went 5-0 ahead.

A drop shot from the Spaniard left Fritz lying on his back, watching Nadal's winner go past him at the end of a 25-shot rally, before the two-time Wimbledon champion turned a final screw with a forehand that put him into his eighth Wimbledon semi-final.