Whilst I'd agree Fognini is the favourite, I still think it'll be quite a close match. Gulbis can be a quality player when he's on form and all of Fognini's recent success has come on clay, could be difficult for him to transition to the hard courts. Either way, should be a good match and either of them will be a potential banana skin for Murray. However, I would still expect Murray to come through that match, setting up an exciting QF with Delpo.