Southampton boss Claude Puel: Nathan Redmond's dismissal changed the game
Claude Puel felt Nathan Redmond's sending off was the pivotal moment of the match as Southampton surrendered the lead to lose 4-1 at home to Tottenham.
Winger Redmond was dismissed in the 57th minute at St Mary's after he was adjudged to have pulled back Dele Alli in the box, although Harry Kane missed the resulting penalty.
Spurs were already 2-1 up at that point after Alli and Kane cancelled out Virgil van Dijk's early opener.
A calm finish from substitute Son Heung-min and Alli's second sealed victory in the final five minutes.
Saints boss Puel told Sky Sports 1: "After the red card, it finished the game. It was too difficult for us to win against 11.
"It's sad because the scenario is bad for us. I don't know if the red card is normal but it changed the philosophy of the game.
"I didn't see the action but from the bench the two players were fighting for the ball. I think it's very hard to take a red card because this scenario changed the whole game for me."
Tottenham manager Mauricio Pochettino played down the quality of his side's display following the win over his former club.
"I don't believe it was one of our best performances (of the season)," he said.
"It was a good result for us. I think we need to be critical because we cannot start the game the way that we started if we want to fight for the top four.
"We need to be more aggressive and more focused from the beginning."