WTA Miami Masters Betting: Jankovic can't solve a problem like Maria

Wednesday's Sony Open quarter-final between Sara Errani and Maria Sharapova went pretty much the way I thought it might, which resulted in a winning wager for this column.

Maria's serve deserted her in the blustery conditions at Crandon Park and she coughed up 14 double faults in a 7-5, 7-5 win, which was comfortably over the 18.5 total games mark for my bet. In the end it took Sharapova two-and-a-half hours to get past the pesky Italian and we were collecting after the first set in that match.

I said yesterday that the other quarter-final between Jelena Jankovic and Roberta Vinci was a tough one to call and it turned into another long battle, with Jankovic coming through in the decider.

It's semi-finals day in Key Biscayne today and first up is Sharapova v Jankovic at 5pm UK time and this one very much depends on which Maria turns up.

If she's going to be serving today at the sort of level that we saw against Errani then Jankovic will fancy her chances, but the Serb has only managed one win over the Russian in their seven previous meetings and that was on grass back in 2007.

It seems unlikely that Sharapova will serve as badly again in consecutive matches and I don't see Jankovic having the power to stay with Maria in many of the exchanges, so my bet in this one is to back under 19.5 total games at around 1.73.

The other semi-final at 1am UK time features Serena Williams and Aga Radwanska and this one is clouded slightly by an injury to Williams, of which the severity is unknown.

Williams rarely discusses injuries, but she did say that her hip was hampering her against Na Li and she had difficulty moving to her right side. With that in mind I don't think it's worth getting involved in this match unless you're taking a chance on Radwanska.

The previous meetings have all gone the way of the American and she tends to blast her way past Radwanska generally when they clash, but with Williams's fitness unknown I'm avoiding that match.

Best Bet: Back under 19.5 total games in Sharapova vs Jankovic at 1.73

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