The first major shock of the men’s Olympic tennis tournament occurred in the early hours of Monday morning when top-seed Novak Djokovic from Serbia crashed out in the first round against Argentina’s Juan Martin Del-Potro 7-6 7-6. Del Potro, who defeated Djokovic in the Bronze Medal play-off match at London 2012, looked more like the player that won the US Open in 2009 and Bronze medal in 2012 and he was hitting his serve and forehand with the same type of venom that won him these accolades.

Djokovic’s dream of adding Olympic gold to an already impressive resume, that includes all four majors and the Davis Cup, ended in tears as the realisation that he may now never achieve this dream due to his age dawned on him. Team GB’s Andy Murray (Evens) seeded two has now firmed up as the favourite to win the tournament and with Djokovic out he will be extremely difficult to stop defending his Olympic title. He’s looked in blistering form so far and with seventh seed Ferrer out (lost to Donskoy) and only three seeds left, fourth seed Nishikori and sixth seed Monfils or ninth seed Cilic (play each other), in his half of the draw it’s looking more and more likely he will become the first ever men’s tennis player to defend their Olympic title and win two Golds.

Belgium’s David Goffin seeded eight (25/1 ½ odds 2 places) is over-priced for the tournament in my view, as Nadal who is in his quarter has been far from consistent so far this season, and could start to struggle by the quarter-final stage as he’s not played any competitive tennis since the French Open due to injury. Goffin clearly thrives playing for his country having helped Belgium make the Davis Cup final last year and if he can reproduce that level of form he’ll be difficult to stop making the final from the top-half of the draw.

Team GB’s Heather Watson is out of the women’s singles as she lost at the second round stage, but tenth seed Johanna Konta was still in with a shout of reaching the fourth round at the time of writing, albeit she was a set down and 5-4 up in the second set against eight seed Kuznetsova, after being a break up at one point. Elsewhere, there was another major upset in the women’s tournament as third seed and French Open champion Muguruza crashed out 6-1 6-1 against Puig of Puerto Rico.

After being knocked out of the men’s double’s tournament with brother Jamie at the first round stage Team GB will still have a chance of winning more medals in the tennis as Andy Murray and brother Jamie both confirmed they will play in the mixed doubles. Andy Murray, who won silver with Laura Robson at London 2012 will partner Heather Watson, while brother Jamie and Jo Konta are the other partnership, but Murray and Watson will only play if there is a withdrawal as there are sixteen teams ranked higher than them.