Nadal resisted the big heart and forehand of Del Potro in a classic to set up what could be another match to savour in the semi-finals against Novak Djokovic. But if and when Djokovic does break serve, or win a set, or save a set point, or do something to fire himself up and sow doubt in Nadal's head, all of that could be turned upside-down in a hurry, the same way their rivalry has been turned upside-down in a hurry in the past.
But the second seed stayed alive by taking the fourth set before the gripping drama continued in an electrifying deciding set in which both players were left diving after volleys and slipping over as they sprinted after blinding winners.
Rafael Nadal and Novak Djokovic is a matchup that brings a lot of memories. He played well. I believe I increased a little bit the level in the fourth and the fifth. "I've tried to build the momentum and I've been very pleased with the way I've been playing in the grass court season".
Nadal described Wednesday's showdown as a combination of "suffering" and "enjoyment" but he was mightily relieved he came back from two-sets-to-one down to reach the semi-finals for the first time since 2011.
Nadal worked the angles and moved superbly from the start, but the heavy-hitting Del Potro frustrated him by saving the first two break-point opportunities of the match before holding to level at 4-4.
In an odd-numbered year, the exit of Roger Federer in a five-set thriller, followed immediately by the triumph of Rafa Nadal in a five-set thriller on Centre Court, would have dominated the sports pages, but unfortunately for tennis fans, England had to go and get to and get beat to Croatia.
"I think I won the best point of the match", the Argentine said with a rueful smile after being beaten by Nadal for the 11th time in 16 meetings. He is one of the more complex players that I have ever seen in our sport, it is always a big test. "I think I can keep doing damage here". Del Potro made him pay as he pounced on his first chance to raise the prospect of another upset on day nine.More news: It's showtime as Trump announces high court nominee Monday
Anderson became the first South African in the Wimbledon semi-finals since Kevin Curren in 1983 and just the sixth in history.
"I think it was great quality tennis, the final set was there were some incredible points".
"The goal is to come back next year". Of course, have been an emotional match. I went to the net.
But in a spectacular showing, the 2017 US Open runner-up reeled off three in a row to surge to within a match of a second grand slam final in 10 months.
"With how I'm feeling physically and mentally, I'm in a very good spot".