Spurs fell behind to a Gary Cahill goal in the first half but raced out of the blocks after the break to take a 2-1 lead.
Two goals from Juan Mata and a late fourth from Daniel Sturridge sealed victory for the visitors, however, to leave Tottenham trailing the Blues by eight points.
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The Belgium international believes that Spurs have shown their ability to compete with the best teams in the Premier League but recognised that they must maintain the pressure for more sustained periods.
"It's been almost the same every time, we have to think about how to put two strong halves together," Vertonghen told reporters. "At the start of the second half, we just totally gelled.
"We pressed their centre-backs, who had been playing much too easily, and had a few good chances. We must talk about how to give more pressure."
Tottenham were enjoying a four-match winning streak before Saturday's defeat but have kept only one clean sheet at home in the top flight this season.