Manchester United could be without star striking duo Robin van Persie and Wayne Rooney for their Barclays Premier League encounter with Tottenham at Old Trafford on Wednesday.
Moyes confirmed Van Persie "is not quite ready" after missing five games with a thigh injury.
Meanwhile Rooney, who missed Saturday's win at Norwich with a groin problem, did not train on Tuesday and will be assessed ahead of the game.
"Robin is not quite ready, we don't think," said Moyes.
"He is not too far away. With Wayne we need to wait and see. He has not trained today so we will need to assess it tomorrow."
It means United will be relying on in-form Danny Welbeck and Javier Hernandez as their strikers when they look to extend their present winning run to seven matches.
And the severity of the injuries may bring an added focus to Moyes' work in the transfer market next month, even though the Scot accepts it is not the greatest time to do business.
"We would always look to try and add players," said Moyes. "But I am not sure January is a brilliant month to do business.
"We will be out there looking as I am sure everyone else will be."