Bradley Dack struck in extra time as Gillingham came from behind to stun Premier League Watford 2-1 and reach the third round of the EFL Cup.
Walter Mazzarri looked set to enjoy his first win as Hornets boss when Odion Ighalo came off the bench to fire them ahead before Dack missed a penalty.
But Mark Byrne struck eight minutes from the end of normal time to level the scores before Dack's heroics as Gillingham beat top-flight opposition for the first time since dumping Portsmouth out of this competition at the same stage in 2005/06.
The Hornets made nine changes from their defeat against Chelsea three days ago with only captain Troy Deeney and Adlene Guedioura keeping their places in the team while, for the visitors, Gills manager Justin Edinburgh named his strongest side.
Watford 1-2 Gillingham
