Monaco are a poor 5th in Ligue 1. I've literally only watched their European games this season. They are impotent going forward. As long as we don't have Szczesny doing an Almunia morris dancing impersonation, we will easily get past them. I'm more worried by Boro, to be honest.
That said, team is deep enough. We started without Chambers, Gibbs, Gabriel, Rosicky, Flamini, Arteta, Oxlade, Walcott and Sanchez amongst others. The team has the requisite depth if not the consistency.