Southampton's youngsters put up a spirited fight with 10-men against Spurs but were denied what would have been a deserved point by a late winner that saw their opponents claim a 2-1 win on Saturday.
Saints took the lead through Tommy-Lee Higgs’s early penalty, but went in level at half-time after Thomas Bloxham equalised.
Matt Carson was sent off after 65 minutes and with Saints down to 10-men for a large part of the second-half, Spurs’ late pressure told with Charlie Sayers’s winner.
The hosts started the game with all the early momentum and Kaya Tshaka’s determination in the area won the hosts a penalty after just two minutes.
It was an ideal chance to claim an important lead with the very first opportunity of the contest and Higgs dispatched confidently from the spot without hesitation.
Saints attempted to increase their advantage and went close to adding to the scoreline on three separate occasions.
After Rio Kyerematen had gone close to levelling the game for Spurs, Rylee Wright struck a fierce shot narrowly wide after good build-up play and full-back Sonnie Davis struck the post after pushing forward to join the next attack.
It was a pleasing start for Carl Martin and Mikey Harris to witness from the technical area, and their side almost had their second goal when Tyler Dibling latched onto a neat through ball but saw his shot blocked well at the last minute.
The Saints attack were combining well and Luke Pearce forced Spurs goalkeeper Aaron Maguire to tip wide with his powerful drive seemingly destined to sneak inside the near post.
Despite the dominance from the home side, Spurs found a way back into the game against the run of play when Bloxham finished coolly inside the area and made it 1-1.
It was Saints who would end the half strongest, although efforts on goal from Dibling and Cameron Bragg could not find the lead they perhaps deserved on the balance of play.
Both sides were trying to gain control in the early stages of the second-half and the contest were still being played at a strong pace.
Saints saw a good chance go begging when substitute Jimmy Morgan failed to connect with his shot from a promising position after Pearce had cut the ball back to him from the right side of the box.
The hosts were dealt a blow when defender Carson was shown a straight red card and for a strong challenge when trying to halt a Spurs counter in its tracks. This meant that Saints had 25 minutes to hold on to a point whilst being a man light.
Having a man extra gave the visitors the chance to pile on the late pressure. Saints held firm at the back for a long period and forced their own attacks when they could with their forwards remaining as willing runners.
One push up field gave them the opportunity to put a corner into the danger area, but captain Jem Hewlett headed wide after rising highest to meet Sonnie Davis’s pinpoint delivery.
However, late heartbreak was to come when Spurs snatched the three points courtesy of Sayers with 88 minutes on the clock.
Saints remain in a strong position in the Under-18s Premier League and are three points behind league leaders Leicester City.