Serena leads their previous matches 7-2. One of Halep’s wins was due to walkover and the other was at the year end championships when Serena wasn’t fit.In Serena’s wins Halep managed just 2 sets.
Serena has not dropped a set so far. She has faced 1 break point in 4 matches which she saved.
Halep has lost just 1 set which was to Babos in the 3rd round. She has faced tougher opponents but has faced a lot more break points and has had to work harder for her holds.
I think Halep has a chance to take this to 3 sets though she will need Serena’s level to drop. It is unusual for even Serena to maintain such a high level throughout an entire tournament.
No value in backing Serena at the start. Hopefully she makes a slow start and we back her when she is a set down.