Mauricio Pochettino's men's three-game winless run has seen them come under pressure for second spot in the Premier League.
Mauricio Pochettino's men went into their game with West Brom towards the end of last month with an outside chance of catching Leicester City at the top of the table. But despite taking the lead against the Baggies, they could only draw 1-1 to leave the Foxes seven points clear with three games to go.
And while taking a 2-0 lead against Chelsea in their next game suggested that they were going to take the race down to the penultimate weekend of the campaign at least, a late fightback from the Blues saw Claudio Ranieri's men crowned as champions.
Though their title hopes may have been dashed, Spurs went into their clash with Southampton knowing that they could take a huge step towards securing second place in the table. But despite going in front once again, they were unable to hold on as Saints clinched a 2-1 win.
And Kane suggested that complacency had perhaps played a role in their inability to turn any of their leads into victories.
"Yes, it has been a long season. We have been fighting hard mentally and physically, but I still think we looked good out there," he told The Sun.
"We played good football, it is just in recent weeks, as people have seen, we haven't finished teams off.
"We have been going ahead and then maybe suffering a lack of concentration."
While the Southampton result was perhaps understandable given how deflated they must have been once the title race was over, squandering the leads in the previous two games perhaps highlights the lack of title-winning experience in the squad.
However, this season will surely help the side for the next time they find themselves in the running with just a handful of games to go. But for now, they will simply be concentrating on ensuring that they finish second and ahead of Arsenal.