Maria and Serena are the only players who have come into this year as 3-time champion at a tournament.
Maria:
2012/2013/2014 Stuttgart Champion
Serena:
2012/2013/2014 US Open Champion
2012/2013/2014 Tour Finals Champion
Who will win a 4th consecutive title this year?
Note:
- Serena is 3-time defending champion at Miami, but since she won her 3rd this year I didn't include it.
- Two players are two time defending champions coming into this year. Sam Stosur 2013/2014 Osaka Champion and Elina Svitolina 2013/2014 Baku Champion.
Petra or Caro on clay. I'm sure Maria is shaking in her boots. I don't think they are credible threats. Not saying it won't happen but there are lower ranked girls who I think have more chance of upsetting Maria at Stuttgart Suarez Navarro and Pliskova come to mind straight away.
Well, we know as of today that Maria won't be defending Stuttgart, beaten by Kerber today. Maria has to defend her FO, which like I said in the Kerber defeat Maria @ Stuttgart thread, will be very difficult this year.
Long ways off to see how Serena does @ the US Open and in the finals of the YEC. HEALTH will be the factor for both of them--especially Serena.