Spurs travel to Upton Park on Monday night and will be keen to extend the gap between themselves and Arsenal in fifth place in the Premier League.
Allardyce is well aware that Spurs have a wealth of attacking talent but says that there is one man in particular who the Hammers will have to stop.
"[Spurs] have been very good this season," said Allardyce.
"The team from an attacking point of view has been outstanding. Recently they have lost their goalscorers, so they've had to rely on one man and one man only to come up with the goods.
"That's Gareth Bale and he's been the major difference between Tottenham and the teams they've played. He's going to need some looking after on Monday night. If we can do that, we nullify a threat that they have."
The last meeting between the two teams finished 3-1 to Spurs in November.