I don't post to much in the tennis section but I've been following the whole Serena saga. I noticed that she's not been at her best so far in this tournament. I looked at the odds for her next match a few days ago and noticed she was at 1.14 which I believe is an indication that something is up. In tennis it's regular to see big favourites impossible to bet at 1.04 1.01 etc but at 1.14 it's a little high.
Looking at the odds again today she's drifted to 1.20. From a little reading about Madison she seems like she's playing in form and has a chance. At 4.50 their could be an upset and I'm happy to get involved. Her last meeting with Serena she got close and forced a tiebreaker. She's got every chance of being competitive.
Madison Keys to win @ 4.50
Tiebreaker in match yes @ 3.75
Serena to win by 2 sets to 1 @ 4.00 (cover)
B365
Good luck