Lukaku was an unused substitute in Saturday's win over Watford, while Martial played 77 minutes but was forced off late with a knock.
However, Solskjaer is confident both players will be available to face Nuno's side.
He said: "Anthony will be fine, he's going to be OK.
"Anthony and Romelu will both be ready for tomorrow, definitely, unless they break down in training today but it looks good, yes."
Solskjaer will also welcome back Victor Lindelof, who was absent for the matchday squad against the Hornets.
He added: "Victor has had a good few days of training now so he'll be ready.