It's day two of the ATP Tour Finals this afternoon in London, with today's action commencing the Kuerten Group. Dan Weston, checks out the matches...
"However, Zverev has reeled off five consecutive head to head wins since the start of 2016, with Cilic's only victory in their match-ups coming when Zverev had recently turned 19, and was ranked almost at the 100 mark."
Federer defeat sees big drift in outright market
We saw two straight-set wins in London yesterday, with Kevin Anderson getting the better of Dominic Thiem, while Kei Nishikori shocked Roger Federer. Yesterday, I discussed the price of the Swiss legend, suggesting he was a little short, but there wasn't quite enough value on Nishikori to make it actionable.
This defeat has big implications for Federer's campaign. Unless Anderson or Nishikori go through the group stage unbeaten, it will mean that Roger has to win both of his subsequent matches - against Anderson and Thiem - to qualify, and even then, it could possibly come down to set difference.
Following this defeat, Federer has drifted to 7.26/1 in the outright market, with Novak Djokovic shortening to 1.491/2 favourite without even having walked onto court.
Djokovic dominating recent meetings with Isner
The world number one will finally do this tonight - not before 8pm - as he takes on John Isner, and Djokovic is priced as a heavy 1.121/8 favourite, having beaten the American big-server in eight of their previous meetings, and the last five in a row.
Looking at the head-to-head data, Djokovic has won these last five meetings relatively comfortably, only losing two tiebreaks and winning six of the 12 sets competed via either a 6-1 or 6-2 scoreline, which is rather ominous for Isner - a man whose game plan will almost certainly be to keep holding serve and hoping for the best in tiebreaks.
In their main tour head to head matches, Isner has only held serve on around 78% of occasions - well below his tour mean in the low 90s - and as would be completely logical, Djokovic's supreme ability on return has a considerably negative effect on his serve numbers. Conversely, he's only been able to break Djokovic's serve around 5% of the time, which again would lead the natural conclusion that any success for Isner will revolve around tiebreaks.
Zverev value in 'must-win' clash
In truth, I think that the price on the big American today isn't hugely out of line, so I'll swiftly move on to the first match on the schedule, which is Alexander Zverev versus Marin Cilic. Despite both players not yet having played a match in the tournament, it has a 'must-win' feel around it, given that a defeat will put the loser in a very tough spot to qualify, given that they still would have to play Djokovic subsequently.
For this match, it's the young German, Zverev, who is the slight 1.9310/11 market favourite, and I actually make this a little value. Their stats across hard and indoor hard combined are pretty similar, and both have relatively unimpressive records indoors in the last year, albeit against a pretty high level of opposition.
Zverev with head to head advantage
However, Zverev has reeled off five consecutive head to head wins since the start of 2016, with Cilic's only victory in their match-ups coming when Zverev had recently turned 19, and was ranked almost at the 100 mark.
Overall, an assessment of their head to head data does show Zverev being able to hold around 6% more than his Croatian rival, although it's also fair to suggest that Cilic hasn't been able to take his chances in these matches as well.
I do feel, though, that this head to head data has a little more weight than yesterday's discussion of Anderson v Thiem, though, and I make Zverev some value at market prices to get his tournament up and running with a victory in his first match.
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Back Alexander Zverev at 1.9310/11 to beat Marin Cilic