Just like the first-team, Sunderland Under-21s were wondering whether a point was sufficient to fulfil their objectives after Stadium of Light frustration.
Substitute Luke Molyneux's last-minute equaliser secured a 2-2 draw for the Black Cats, yet this was really a game where Andy Welsh's side required all three points to keep their U21 Premier League title hopes alive.
With one game left to play, Sunderland are five points ahead at the summit, yet second placed Manchester United boast a significant five games in hand.
As was the case for the first-team 24 hours earlier, it was a case of what-might-have been after a succession of missed chances.
George Honeyman spurned the opportunity to give Sunderland a 17th minute lead after playing a lovely one-two with Carl Lawson on the edge of the area.
Honeyman received the return ball to the right of goal, but with only Paolo Gazzaniga to beat, he fired a right-foot into the side netting.
Tom Beadling tested Gazzaniga just before the half-hour mark with a curling free-kick from 25 yards which the Southampton keeper parried high to his right.
Those had been the only two meaningful moments of the first half, but within 10 minutes of the restart, it was Southampton who went ahead.
Sunderland keeper Max Stryjek couldn't hold Olufela Olomola's shot and Sam Gallagher latched onto the rebound to cushion a half-volley into the corner of the net.
Stryjek prevented Gallagher doubling Southampton's lead just after the hour mark when the striker got the wrong side of George Brady, but saw his shot saved by the legs of the Sunderland keeper.
Mikael Mandron should have levelled for Sunderland in the 73rd minute when he got above his marker from Rees Greenwood's corner, but couldn't get the right placement on his header and Gazzaniga was able to save.
Lawson then curled a shot just over the top after Mandron's lay-off on the edge of the area.
Moments later, Josh Sims had a golden opportunity to level at the other end, but slashed a shot wide from 15 yards out with the goal at his mercy.
Sunderland immediately made Southampton pay when Honeyman levelled after Mandron fed him down the left-hand side of the area and the midfielder fired into the far corner.
That goal prompted Sunderland to push hard for a winner - Mandron's header cleared off the line after he had met Greenwood's free-kick.
But with three minutes to go, Sunderland were hit by a sucker punch, when Ollie Cook headed home from a corner.
Sunderland immediately replied though; Greenwood finding space down the left-hand side of the area and delivering a superb ball across the face which was turned in at the far post by Molyneux - only seconds after he was introduced from the bench.
Sunderland: Stryjek, J Robson (Molyneux 88), T Robson, Agnew, Brady, Beadling, Lawson, Wright (Nelson 88), Mandron, Honeyman, Greenwood. Subs not used: Hume, Talbot, Casey.
Southampton: Gazzaniga, Gape, Vokins, Reed, Cook, Jones, Olomola, Little, Gallagher, Hesketh, Sims. Subs not used: Bakary, Lewis, Johnson, N'Lundulu, Rowthorn.