London - Mauricio Pochettino got the response he demanded from a spirited Spurs as they defied Serge Aurier's first-half red card to hold out for a vital 2-1 win over Southampton on Saturday.
Harry Kane's winner secured a first win in four games as Tottenham moved back into the Premier League top four despite playing for over an hour with 10 men.
"Every time we compete we need to put this character," said Pochettino. "In some games we struggled to show that.
"I am so happy for them, we have an unbelievable squad, but we need to recover the spirit we showed today."
Spurs had won just two of their opening eight games of the season and needed to make a statement after crashing out of the League Cup to fourth-tier Colchester on Tuesday.
Son Heung-min was Spurs' biggest threat early on and should have had an assist early on when he squared for Tanguy Ndombele, but the French international's prodded effort was deflected over.
Moments later, the same two players combined for the opening goal as Son's cut-back was driven goalwards by Ndombele and his shot had too much power for Angus Gunn in the Southampton goal.
However, rather than building on their advantage, Tottenham gave themselves a mountain to climb with two moments of madness.
Firstly, Aurier needlessly pulled down Nathan Redmond to see his second yellow card in four minutes to leave his side a man down.
And then with cool heads needed to see out the lead till half-time, Hugo Lloris tried to perform a Johan Cruyff turn inches from his goal line and was dispossessed by Danny Ings, who had the simple task of nudging the ball across the line.
Having shown why they had won just four games in 17 prior to this weekend, Spurs swiftly produced a glimpse of what they are capable of at their best as they retook the lead before the break.
Kane won a header on halfway to spring a counter-attack. Son and Christian Eriksen exchanged passes before the latter found the England captain to drill low into the corner.
Minus a man, Tottenham had to hold onto their lead after the break but were rarely troubled by the impotent visitors apart from at set-pieces.
"We cannot be happy because the chance to take something here will not be so big again," admitted Southampton boss Ralph Hasenhuttl.
"1-1 against 10 men, to be clinical is the next step of development we need to take."
Lloris made amends for his earlier error with a fine stop to turn James Ward-Prowse's long-range free-kick over.
And the France captain then produced an even better stop to claw Maya Yoshida's powerful header off the line.
"I don't want anyone to blame him in this action, you need to blame me because I demand him to do what he is doing," added Pochettino on Lloris's error. "He is so strong mentally."
Spurs' threat on the counter-attack was reduced by the removal of Son on the hour mark, but Kane could have sealed the three points when he fired just wide after a brilliant solo run six minutes from time.