Nitto ATP Finals: Four stories that headline season-ending finale

Defending champion, Alexander Zverev not in a favourable position

Can Alexander Zverev defend his title in London?

Alexander Zverev's season has been a dampener yet again. The German who won the ATP Finals title last year has had a below par showing this year. Clinching just one title this season in Geneva, the 22-year old is actually not in a position to create any noise on this stage.

Dealing with numerous off-court problems which reflected on his tennis, the German surely knows about the work he has on hands if at all he has to have a shot to go deep in London. After a fourth round finish at the Australian Open, Zverev reached the final in Acapulco and then fell to Nick Kyrgios in the title clash.

The German did make the quarter-final at the French Open but lost in the fourth round at the US Open to Schwartzman. Since some brilliant tennis at the Shanghai Masters where he reached the final but lost to Medvedev, Zverev has been inflicted with early exits both at Basel and the Paris Masters.

And while all the drama unfolds this Sunday, let the countdown keep fans hooked.