Collonges blow for Macaire Promising French chaser Heros Collonges has suffered an injury setback and is likely to miss the Cheltenham Festival, it was revealed today.Guillaume Macaire`s seven-year-old was a leading contender, along with stable mate Japhet, for the Royal & SunAlliance Chase next month and was expected to have his second start in Britain in the Amlin Reynoldstown Novices` Chase at Ascot on Saturday.He comfortably accounted for Duchamp at Kempton on his last outing but Macaire said today: 'He has a problem and it is impossible for the moment to train on with him.'He will probably miss Cheltenham. It is not a big, big problem but for a safety attitude it is safer to stop work with him at the moment.'It is not possible to have a perfect view of the future now because the problem came only two days ago.'It is a problem with his right leg and it is necessary to stop all the work now and it is impossible to continue on the route to Cheltenham because without work you cannot have a horse in perfect fitness.'Cheltenham is very testing and a horse needs to be at full fitness.'Coral removed Heros Collonges from their market on the Cheltenham race and shortened Japhet to 4-1 favourite from 6-1.Macaire is confident his star can overturn his recent Newbury defeat by Frosty Canyon - the first of his career - at Cheltenham.'Last time he was beaten unfortunately for the first time in his career,' said Macaire. 'It was probably my fault as I was too confident with the horse.'He blew hard for maybe an hour after the race, he was not ready in fact.'It was also his first time over that distance (three miles) because in France he has not run over more than two miles, six furlongs.'The horse has recovered very, very quickly and he is very well at work now.'He is ready for another run and I have two alternatives - a three-mile novice chase at Kempton next Friday (Weekender Novices` Chase) and on Saturday the Pendil Novices` Chase.'But the Pendil is over two miles and four furlongs and maybe it would be better to prepare him over three miles.'Coral also trimmed Artic Jack in betting on the SunAlliance and trainer Nicky Henderson today confirmed his charge a runner in the Reynoldstown.Royal & SunAlliance Chase, Coral betting: 4-1 Japhet (from 6-1), 9-2 Harbour Pilot, 8-1 Artic Jack (from 12-1), 10-1 Frosty Canyon, 14-1 Colonel Braxton, 16-1 Richter Scale, Maximize, 20-1 Southern Star, Gola Cher, Risk Accessor, 25-1 bar.