PRESSURE can get to the best of players no matter what sport you are playing.

That was certainly the case when Serena Williams suffered her shock defeat to Roberta Vinci in the US Open Tennis Championships semi-finals.

For all the world, it looked as though the formidable force of Williams was heading towards history in New York and the calendar Grand Slam.

Only three players in the women’s game have ever achieved that landmark, the last being Steffi Graf back in 1988.

That just proves exactly what Serena was up against and why pundits, myself among them, shouldn’t have expected her to just waltz into that elite club.

Not that it wasn’t any less of a shock, with her having come so close.

Serena has been so dominant in recent years that she has appeared unbeatable.

Such an achievement would have been a fitting accolade for a player who has enjoyed such a glittering career.

But it wasn’t to be and it remains to be seen how much missing out on history will affect her.

It is also just possible that Vinci’s triumph at Flushing Meadows will give the other players below the powerful American in the WTA rankings the belief to do the same.

Few have been able to get near her in recent times but this shows that there might just be a chink in her armour after all?

This could be the beginning of the end for Serena.

But, with the talk of the calendar Grand Slam out of the way and the pressure now eased, it could also mark the start of a determination to go one better and complete the set in 2016.