Leeds suffered a humiliating FA Cup third round exit as League Two Crawley Town outplayed their Premier League opponents to win 3-0 at Broadfield Stadium on Sunday.
Marcelo Bielsa's men have made an impressive start to life back in the top-flight after a 16-year absence with the Argentine's attacking brand of football winning plenty of admirers.
But Bielsa is still yet to win a FA Cup tie in his three seasons in charge and was punished for resting a number of his key men.
Illan Meslier, Stuart Dallas, Luke Ayling, Mateusz Klich and Patrick Bamford were left out and in-form Crawley took advantage to extend their own unbeaten run to 10 games in all competitions.
Bielsa made three substitutions after a goalless first-half, but rather than kick the visitors' into gear, it was Crawley who took control in the second-half.
Nick Tsaroulla's stunning individual run and finish opened the scoring on 50 minutes.
Just three minutes later it was 2-0 as Ashley Nadesan's shot snuck underneath the hapless Kiko Casilla.
Jordan Tunnicliffe then rounded off a famous win for the fourth-tier side when he smashed into the roof of the net after Casilla could only parry Nadesan's initial effort.
Crawley could even afford the luxury of handing a debut to reality TV star Mark Wright in stoppage time.
Wright, who started his career at Arsenal and Tottenham before going into television, is making a documentary with the club to see if he can make it as a professional player.