Arsene Wenger lost an FA Cup third-round tie for the first time as holders Arsenal were stunned 4-2 by Nottingham Forest on Sunday.
Wenger has lifted the famous trophy on seven occasions – including three of the last four years – but saw his much-changed side undone by two Eric Lichaj goals along with penalties from Ben Brereton and Kieran Dowell in a classic cup tie at the City Ground.
The likes of Alexis Sanchez, Mesut Ozil and Alexandre Lacazette were all rested as Theo Walcott and Danny Welbeck were afforded rare starts in an unfamiliar Arsenal XI.
But Wenger's plan backfired against a Forest side who are still without a permanent manager following the sacking of Mark Warburton last month.
Lichaj's headed opener was swiftly cancelled out by Per Mertesacker but the American restored the hosts' advantage with a stunning volley just before half-time.
Forest had a cushion when 18-year-old Brereton showed composure beyond his years to beat David Ospina from the spot following a Rob Holding foul on Matty Cash, but a late Welbeck strike threatened to make it a tense last 10 minutes for the home side.
However, Gary Brazil's men were awarded a second penalty when Mathieu Debuchy brought down Armand Traore from behind, allowing Dowell to convert from the spot, and Joe Worrall's red card mattered little as Forest held on for a famous win.
The result represents Arsenal's first third-round defeat since they lost in a replay to Sheffield United eight months prior to Wenger's appointment in 1996.