Tsonga has been showing signs of fatigue recently, and has beaten Andy only once before. Yes it was in the 2nd round of the Australian, but it was 4 years ago. It will be Andys to lose and he shall have time to recover in a 5 setter, should Jo go on one of his hot streaks that he can never quite sustain for an entire match.
Tsonga pulled out of Kooyong with fatigue but looking at how he has cruised through his last 2 rounds that would have seem to be a move that was made out of caution more than anything.
I agree Tsonga is a very good match up for Murray I feel like whatever he throws at Murray, Murray has the craft and skills to kind of handle it and throw it back to him, that loss to Tsonga was actually the 1st round Tsonga was playing lights out.
I would expect Murray to win if they played in 4 or 5 sets, the only thing I would say though, is that matches apart from one or two have generally been pretty tight, and over the last 6 months Tsgona has been playing some of the best tennis of his life, these two have not played in that time so it would be an interesting one.