There are currently six spots available in the Tennis Masters Cup in Shanghai at the end of the season. Roger Federer and Rafael Nadal are already assured places in the elite eight-man line-up, which leaves Ivan Ljubicic, Andy Roddick, Nikolay Davydenko, James Blake, Tommy Robredo, David Nalbandian, Marcos Baghdatis and Mario Ancic to fight it out for the remaining places.

With few of the competitors in action last week, the Indesit ATP Race rankings are unchanged this week as far as the leading contenders are concerned.

Ljubicic is a mere 2 points ahead of Roddick, and less than 100 points (88 if you're being picky) cover the entire eight, so it's safe to say things are pretty tight. If anyone slips up in the next few weeks they'll just have to sit tight, cross their fingers and hope their rivals have a slip-up.

Only Ancic was in action last week, in ATP Tokyo. Ancic has been slowly but surely sneaking up on his rivals over the past few tournaments and could turn out to be a dark horse. Being 25 points behind Baghdatis, his nearest competitor, at the start of the week, he needed a good week in Japan, particularly as Baghdatis is currently sidelined with a shoulder injury and unable to play. Ancic didn't get the tournament he hoped for, coming up against an inspired Tim Henman in the quarter-finals. The gap was closed by just four to 21 points. Fortunately for Ancic, Djokovic was the only player below him in the Indesit ATP Race to make any substantial point gains. He won the title in ATP Metz, but as he is 100 points below Ancic, he will need an exceptional end to the season to displace him from the running.

This week, most of the contenders are competing. Davydenko heads to his home tournament in Moscow, Blake is the second seed in Stockholm to defend his title, and Ljubicic, Roddick, Nalbandian and Baghdatis are in action in Vienna. Just to complicate matters even further, other players who are outside bets for Shanghai are also in action in Vienna, such as Tommy Haas, Fernando Gonzalez and Novak Djokovic, but they would need to go far into the tournament at the expense of the definite contenders.