Saints suffered a dramatic FA Cup defeat against Millwall at St Mary's.
Former Salisbury City and AFC Bournemouth winger Liam Feeney came off the bench before scoring an outstanding winner in injury time.
The Londoners took a 17th-minute lead through Liam Trotter, who fired in from the edge of the box.
But Saints looked to be heading for a fifth-round tie with Bolton Wanderers when Adam Lallana hit a brilliant equaliser before half-time and sub Rickie Lambert hit his 20th of the season.
But former Saint Dany N'Guesan headed in an 80th minute equaliser.
And then Feeney raced down the left wing and cut on to his right foot before finding the top corner.
Full match coverage in tomorrow's Daily Echo