Chelsea are in danger of seeing their season unravel if their "downward spiral" continues, according to the club's former winger, Shaun Wright-Phillips.
Antonio Conte's side have seen their lead at the top of the Premier League cut from 10 points to four with only six matches left to play.
Defeats to Crystal Palace and Manchester United have allowed Tottenham, who are on a seven-game winning run in the top flight, to pile the pressure on Chelsea ahead of an FA Cup semi-final showdown between the pair on Saturday.
Wright-Phillips, who won the title under Jose Mourinho in 2006, has warned that the Blues will face some nervy moments if Spurs continue their form.
"In a Premier League race it's never over until it's over," Wright-Phillips told 888sport.
"At one stage it was an 11-point gap and now it's down to four points so that is nerve-wracking for the players. As we would say, it's 'squeaky bum time'.
"It could be that they're on a downward spiral. As big as the characters are in that dressing room I still think there will be a spell where they might get nervy if Tottenham keep going as they are."