The Portuguese winger returned to action quicker than expected for last night's Champions League win over Marseille after receiving a nasty gash on his leg in the league loss to Liverpool two weeks ago.
But he admits that playing last night could put him in doubt for the visit of the Trotters.
"I played against Marseille but maybe I couldn't play tomorrow because I have so many injuries. I always finished the game sore because I have had three or four tackles on the same part of my ankle," he said.
"My leg is OK [but] it is not 100% and the confidence is not the same.
"I know players always like to tackle me, so I have to be careful. That is why my football was not the best. But it is great to be back.
"Now I am just thinking about the next game when I think I will be much better."