Jake Hesketh curled into the top corner to give the Saints a 64th-minute lead, but Nabil Bentaleb volleyed home from 12 yards to restore parity with 13 minutes remaining.
Southampton U21s: Gazzaniga, Martina, Debayo (Vokins 6), Reed, Mugabi, Jones, Sims, Gape (c), Gallagher, Juanmi, Hesketh. Substitutes (not used): Olomola, Little, Bakary, Lewis (GK).
Spurs U21s: McGee, Walker-Peters, Georgiou, Amos, Carter-Vickers, Bentaleb (c), Miller, Winks (Lesniak 81), Harrison (Sonupe 70), Onomah (Goddard 81), Walkes. Substitute (not used): Voss (GK).
Below: Anthony Georgiou takes on Josh Sims