Bet against "average" players defending their titles

Truths, Lies and Tennis Statistics / Matthew Walton / 29 November 2007 / Leave a Comment

"Magical" Matthew Walton tells us why top players defend their ranking points and why average players don't...and how this helps you with your betting

The process of finding winners can take us down many avenues of investigation.

As a result strategies, or systems, can be framed around numerous factors including a player's age, nationality, seeding, recent form, his record in similar tour events, whether he has won a title before or not and so on.

Most of these factors have been discussed in previous articles and here we'll add one further area of study to the mix, namely the effect of being the defending champion of a tournament - how much weight should we give this factor when trying to locate winners?

Firstly, it's worth noting that players have a vested interest in defending any titles which they have won. The way in which the ATP Rankings are calculated is on a rolling 52-week cycle (which, please note, is different from the ATP Race which is calculated on a calendar year basis).

To use a rather simplified example, if Roger Federer was to win the first event of the year in Qatar on January 8th the points gathered there would apply to him until January 7th of the following year. They would then drop off and his ranking would fall. The way to prevent this fall, of course, would be to win the event again and so get back the same number of points which he'd just lost from the previous year.

It's a bit like topping up a bucket which has a hole in the bottom. If you replace the water as fast as it leaks out then it'll stay at a constant level (or, in this case, maintain a steady ranking position).

Clearly some players take more heed of this fact than others. Whether that's due to illness, injury, sponsor's commitments or whatever, not every player will defend his title even though they have a vested interest in doing so.

Looking at the stats for the last five years we note that players may well be coming more aware of the need to keep rankings high. After all, rankings make for better seedings in the bigger events and better seedings make for easier matches, for better results, for more ranking points and so the cycle repeats itself.

Back in 2001 there were only 7 wins by defending champions, in each of 2002, 2003 and 2004 there were just 6 repeat winners. That shot up to 12 in 2005, then a high of 15 in 2006 and a respectable 14 this year.

It has to be said that a few usual suspects crop up more than once on these lists. Roger Federer has defended titles in 2007 (5 times), 2006 (6), 2005 (7), 2004 (3) and 2003 (1) and Rafael Nadal has achieved the feat four times in each of the last two years.

There are also multiple entries for the likes of Nikolay Davydenko, Andy Roddick, James Blake, Lleyton Hewitt and Carlos Moya.

As you can see, none of these players could be considered 'average' - all are top ten players with the exceptions of Moya and Hewitt both of whom have certainly been there and bought the T-Shirt.

Simply put, even when you widen the list to all players who have recorded wins as the defending champion, you're not looking at a poor bunch. Only players such as Almagro (2007), Zabaleta (2004), Rusedski (2005) and Schalken (2003) would fall into the 'good' as opposed to very good category.

This would suggest that if a player, what we might consider an 'average' player, wins an event he won't defend his title the next year. Maybe he got lucky with the draw, perhaps he just played great tennis that week, it doesn't matter. The data suggests that whilst he may well go on to win more tournaments in the future, any 'average' player who wins a tournament can pretty much be scrubbed from calculations for the next year's event. He won't be good enough to defend his title, no matter how many ranking points that win might save him.

This study adds another piece into the photo-fit we are trying to create of the typical tour winner. The clearer the picture becomes the more ably we will operate on the exchanges. For sure we can throw too many criteria into the mix and confuse the issue but key elements such as the ones we have discussed here in recent weeks are all valid areas of research.

Are there any particular strategies that you employ or would like investigating? By all means let us know if you have a particular system which helps you to find winners.