Voy Por Ustedes heads a field of five declared for the Betfair Ascot Chase at the Berkshire track on Saturday.

The eight-year-old, trained by Alan King, is dropping down to two miles five and a half furlongs in a bid to open his account for the season.

The three miles of the King George VI Chase stretched the 2007 Queen Mother Mother Champion Chase hero's stamina when he finished third to Kauto Star.

Kauto Star took this prize 12 months ago and his trainer Paul Nicholls looks to Gwanako for victory this time around. Nicholls' six-year-old took a graduation chase over this course and distance in December.

David Pipe, fresh from his triumph with Madison Du Berlais over the Nicholls-trained Gold Cup winner Denman at Kempton last weekend, saddles Tamarinbleu.

The nine-year-old captured the valuable Victor Chandler Chase over two miles and one furlong here last winter.

Completing the quintet are Nigel Twiston-Davies' Knowhere and Bob Buckler's The Sawyer, who was successful in a handicap chase at Cheltenham last time but is set to run at Chepstow on Thursday.