Tuesday's wagers in the Ladies Singles at the 2013 French Open gained no reward and despite correct working out, somehow the sums ended up wrong.
I said that Sara Errani would push Aga Radwanska to three sets, but the Italian did it in a tie break in the second set instead, while my idea of siding with Sveta Kuznetsova against Serena Williams was most unfortunate.
Instead of winning the three games required in set one, the Russian won them in sets two and three, which was pretty galling. Had Sveta converted the break points she had in the very first game of the match, it could have been so different.
Williams, after running through that opening set 6-1, totally lost the plot in set two and had to stave off numerous break points to avoid going 3-0 down in the decider. Kuznetsova didn't take her chances and after battling herself for two sets, Williams finally managed to get over the line.
Wednesday's two remaining women's singles quarter-final matches see Jelena Jankovic take on Maria Sharapova at 1pm UK time on Court Philippe Chatrier, while Maria Kirilenko faces Vika Azarenka at the same time on Court Suzanne Lenglen.
Sharapova has had much the better of the career meetings with Jankovic, having won six of their seven completed matches, but the only time they were scheduled to play on clay was when Maria withdrew ahead of their 2008 Rome semi-final.
Maria destroyed JJ two and one when they met on slow hard courts in Miami a couple of months ago. She hasn't dropped a set in this tournament since losing a tie break to Klara Zakopalova in last year's fourth round.
Jankovic impressed in the last round with a comfortable win over Jamie Hampton, but that hasn't gone very far in convincing me that the Serbian will have much of a chance on Wednesday.
I think Sharapova will win this one in straight sets, so the -1.5 sets at around 1.57 would be the bet in this.
The two protagonists in the other semi-final are also meeting for the first time on clay and for the sixth time in total. Kirilenko last defeated Azarenka back in 2007 and Vika has won the most recent three in straight sets on grass, hard and indoor hard.
A few judges were siding with Fran Schiavone to take down Azarenka in the last round, but not me. There's a feeling that Kirilenko has done very well with the ability she has to reach three grand slam quarter-finals, of which this is the third.
Vika is into only her third French Open quarter-final and having lost the first two she'll be extra keen to make the last four here for the first time. With the world number 12 on the other side of the net, I doubt she'll pass up this opportunity.
The Belarusian has improved on the dirt - which is far from her favourite surface - as the tournament has gone on. I think this one will be over in less than 19.5 total games at a price of 1.80.
Back Sharapova -1.5 sets to beat Jankovic at 1.57
Back under 19.5 games in Azarenka/Kirilenko at 1.80
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