Venus shouldn't be underestimated, she's a great champion and competitor and she deserves respect which Masha will undoubtedly give her.
But in reality Masha SHOULD win this match (if it does happen) bar the injury worry which by round 3 she should've shook off the rust, she is much stronger than Vee nowadays and I think winning in 2012 (regardless of the surface) should give her a mental edge. Anyway I'm just looking forward to her first round soon
