Defending champions - what are the chances of lightning striking twice?

Truths, Lies and Tennis Statistics / Matthew Walton / 13 September 2007 / Leave a Comment

"Magical" Matthew Walton looks at whether there's long-term value in backing previous winners of the different tournaments and is so, which ones?

Selecting a player to back in the outright market of a tournament includes the assessment of numerous factors - current form and fitness, the strength of the field, severity or ease of the draw, ability on the surface and that's just to name a few.

One other factor, which many recognise, is that of previous tournament form. In short, has the player any past success in the particular event in question - and specifically winning form?

There have been 51 tournaments completed on the ATP tour this year. These 51 events have been won by the defending champion on 11 occasions (21%). It follows that if the average price of those 11 players was around the 5.00 mark then simply backing the defending champion in every event would have made you a profit (for the sake of argument we are presuming that all defending champions return to defend their titles).

However, these 11 wins break down the following way :-

4 Grand Slams - that's Federer in the Australian Open, Wimbledon and US Open plus Nadal in the French Open. All four Slams have gone to the defending champion.

2 Masters Series events (of the 7 played) - both by Nadal, at Rome and Monte Carlo.

2 Gold Series events (of the 7 played) - Nadal, again, at Barcelona and Tommy Haas (backable at around 4.50) in Memphis.

So from a total of 4 Grand Slams, 7 Masters Series events and 7 Gold Series events (18 tournaments) we've had 8 defending champions obliging = 44%

From the remaining 33 'regular' ATP events only 3 have been won by the defending champion - James Blake (6.50) in Sydney, Andy Murray (4.50) in San Jose and Nicolas Almagro (4.50) in Valencia - representing a pretty poor 9% success rate.

The conclusion drawn from this rather simplistic approach suggests an element of caution on the part of the backer.

Yes, defending champions in the better quality events are more likely to retain their titles but they almost always tend to be very short prices. In the normal, run-of-the-mill tournaments you'll find bigger prices but a much lower strike rate.

Significantly better results are achieved when the sample group is broadened. For example, study the players who have made the final, whether winning or losing, in the same event in any of the previous three years.

Clearly this approach increases the potential number of options to the backer - from one player up to a possible six - but it does boost the location of winners.

We take the 51 events this year. Of those, take the same 18 'blue riband' events as above and these have had 13 winners (72%) who had made the final of the same event in one of the three previous years. They might have won or lost the final but the point is they had solid past tournament form.

Of the 33 'lesser' events the figure is 11 winners. That's 11 champions in 2007 who had made the final of the same event in any of the past three years. This equates to 33% which is a sizeable leap from the 9% we had when solely discussing defending champions.

For sure, the number of suspects could have risen six-fold but the point is that the winner, in one out of every three events, has significant tournament form.

The overall impression given by these figures is that tournament form does play a significant part in the selection of winners. That said, whilst backers ignore such statistics at their peril, they can also over-estimate their importance.

For the sake of uniformity in this analysis we have presumed that the defending champion always defends his title, that isn't the case.

What we know is certain players do have favourite events and defending champions do very often play well in the follow-up tournaments - partly because of these preferences but also because of other factors (notably they are defending a ruck of ranking points).

The use of tournament form, and defending champion form, is a useful tool in the armoury of the backer - more so when used in tandem with other sources of information.