Kevin Anderson became only the third man to come from two sets down to beat Roger Federer at a grand slam as he pulled off an epic comeback to knock out the defending champion in the Wimbledon quarter-finals.
Anderson achieved something only Jo-Wilfried Tsonga and Novak Djokovic had done before as he fought back to prevail 2-6 6-7 (5-7) 7-5 6-4 13-11 in an epic match that lasted four hours and 13 minutes.
Federer had not dropped a set in his serene run through to the last eight at the All England Club, and the defending champion appeared poised for a relatively routine win when he went match point up in the third set.
Anderson turns the tide in his favour
But the big-serving and obdurate Anderson was undaunted by the situation, staying alive before turning the tide in his favour, preventing Federer from breaking his own record for consecutive sets won at SW19.
The previously unlikely prospect of Anderson completing an unbelievable recovery appeared a more realistic possibility when he ensured the increasingly frustrated eight-time champion would have to go the distance to reach the last four.
Neither player's defences looked penetrable in a tense and absorbing fifth and for the most part there was little sign of the stalemate ending.
However, it was Federer who was stunningly the first to falter and Anderson took advantage to book a semi-final clash with either John Isner or Milos Raonic.
Federer immediately went 40-0 up on the Anderson serve in the opening game, taking the second of three break points when the eighth seed hit a backhand wide before easily holding to love.
Anderson struggled to make any impression on Federer's serve as the Swiss' guile saw him dominate, breaking for a second time when a deep forehand could only be returned long by the South African.
A delicate half-volley gave Federer the opening set in 26 minutes, but two games into the second Anderson had the initiative, snatching the first of two break points as he turned up the power, the world number two netting a backhand.
Federer eventually stemmed the tide with a love hold, and the set was back on serve when Anderson failed to clear the tape with a forehand after saving two break points.
Anderson spurned the chance for another break when he rammed a forehand into the net and was forced to settle for a tie-break after Federer recovered from 30-0 down in the final game of the set.
Despite winning three tie-breaks against Gael Monfils last time out, Anderson was second best in the shoot-out. A flourishing Federer backhand put him 4-2 up before a similarly impressive forehand gave him three set points, taking the third following a pair of uncharacteristic errors.
A third set low on opportunities came to a frenetic conclusion. Anderson survived match point and then broke with a backhand down the line, going on to take the match to a fourth as Federer spurned three break points, an ace ending his run of 34 consecutive sets at Wimbledon.
Any thought of the third being an anomaly was soon put to bed by Anderson in the fourth, a scorching forehand return giving him two break points.
Federer saved one but could only flail a forehand into the net on the second, with his exasperation becoming evident as Anderson subsequently held to love.
Anderson's attempt to serve out the set was not without drama but, though Federer brought up a break-back point, a searing cross-court backhand saved it and a forehand into the left corner secured a decider.
Shock of the tournament
The shock of the tournament appeared to be edging closer when Anderson moved 30-0 up in the third game, but Federer relied on his serve to salvage a hold, doing the same four games later to dig himself out of another hole after Anderson had also recovered from 30-0 down.
Federer was unable to snatch an unexpected chance from 40-0 down as Anderson's resilience again came to the fore in the eighth game, and that proved his last opening as he was ultimately worn down.
A double fault gave Anderson a break point, Federer then firing into the net, and his hopes of a record-extending ninth Wimbledon title were ended as he was unable to return a huge serve down the middle.