Eric Dier conceded Tottenham only had themselves to blame after a late collapse at bottom-of-the-table Southampton meant they were forced to settle for a 3-3 draw.
Spurs led 3-1 with 13 minutes remaining, but Theo Walcott got a goal back for Saints before James Ward-Prowse converted a stoppage-time penalty after Pape Sarr was adjudged to have fouled Ainsley Maitland-Niles.
Antonio Conte appeared to be furious at the decision, but Dier acknowledged the result should have already been put to bed by that point of the match.
"We only have ourselves to blame," the Spurs defender told Premier League Productions.
"Sloppy mistakes. We lost possession easily and didn't have control of the game at 3-1 when we should have.
"We conceded really poor goals and should not let them back into the game. They lost both their centre-backs [to injury] and we should have caused them a lot more problems."
The draw for Spurs on Saturday means Manchester United and Newcastle United continue to hold the upper hand in the race to secure a Premier League top-four finish.
Spurs are a point behind Erik ten Hag's side having played two games more, while they lead Newcastle by just two points, despite the Magpies holding two games in hand.
"There will be lots of ups and downs for everybody fighting for top four and relegation," added Dier.
"It will definitely go down to the last couple of weeks of the season, and we need to find some consistency."
2+2 - Southampton vs Tottenham is just the second game in Premier League history to see both sides make two substitutions each before half time, after Newcastle vs Wigan in April 2006. Update. https://t.co/KlzwRCMjMF— OptaJoe (@OptaJoe) March 18, 2023
Ward-Prowse held his nerve to score past ex-Saints goalkeeper Fraser Forster, capping an influential performance that had seen him rack up a game-high five key passes prior to the vital spot-kick.
"Yes, there was a lot of pressure," he said about the penalty.
"I know Fraser very well, he used to be my next-door neighbour, so I've taken a few penalties against him in my garden with my little boy, so we have something going on there."
Asked if Saints can avoid relegation, he replied: "Of course. You have to have belief. We're in the mix, and we have to be positive and look up the table."
And Southampton manager Ruben Selles was thrilled to take momentum into the break in club action.
"You know the feeling when you go to the international break that you did something big," he said.
"It feels great, and we need to take all that we can from it; it is a great moment. The players showed character. It feels great and I'm very proud.
"I don't think we deserved to be 3-1 down, but we showed character and the crowd helped us. Once we scored the second one, we had all the energy.
"The players want to fight for each other."