World number one and defending champion Roger Federer of Switzerland was grouped with Australia's Lleyton Hewitt in the draw on Wednesday for the season-ending ATP Tennis Masters Cup.

Federer, the winner of three Grand Slams this season, and Hewitt will be joined the Red Group by Spain's Carlos Moya and Argentina's Gaston Gaudio.

Topping the Blue Group will be world number two Andy Roddick of the United States, with in-form Russian Marat Safin, Britain's Tim Henman and Argentina's Guillermo Coria completing the elite eight-player field.

Play in the $4.5 million tournament begins on Monday with the top two in each group advancing to the semi-finals.

Federer has not played since injuring his thigh preparing for his home tournament in Basel last month and he will be relieved to have avoided Henman, who holds a 6-3 record over the Swiss in head-to-head meetings.