Agbonlahor, N'Zogbia and Vlaar all doubts for Tottenham
Agbonlahor has been absent from the past three games - Norwich, Liverpool and Chelsea - with a thigh injury picked up in training.
N'Zogbia injured his knee in training on Thursday while Vlaar has been absent for the past six games with a troublesome calf problem.
Lambert admits he's eager to have as big a squad as possible to pick from in this busy festive period.
But he doesn't know yet whether Agbonlahor, N'Zogbia and Vlaar will be part of his plans.
He said: "Gabby? I'm not so sure. Gabby is still feeling it.
"Charles? I'm not so sure either. Charles hurt his knee on Thursday.
"And we'll see where Ron is too."
Lambert says he'll analyse the Chelsea loss ahead of the Boxing Day clash against Tottenham - but not go overboard with it.
He added: "You analyse it. But you can't overanalyse it otherwise it will drag you right down. You get to a point where you have to let it go.
"I will think about it for the next few days but we have another game coming up for us to rectify that.
"How do we get over it? We just go out and try to win the next game.
"There's no magic formula. You just go out and try to win. It's how we react - that's a good marker of a good team, how we react to it.
"The fans have been right behind us, even against Chelsea. They will come in their thousands against Tottenham."
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