Imperial Commander out of Gold Cup

Imperial Commander won the Gold Cup in 2010 (Getty Images)

If his defection could hardly be counted the most surprising, it certainly will not be the last. As such, Nigel Twiston-Davies will have sent a shudder through every rival trainer when he scratched Imperial Commander from the Cheltenham Gold Cup.

Few, after all, will be preparing more talented horses for the Festival next week. But they will be hoping that their own charges prove more robust – or fortunate, at any rate – than Imperial Commander, who beat Denman and Kauto Star in the 2010 running. The following year he broke a blood vessel, and then disappeared for 22 months before resurfacing at the trials meeting in January. A narrow defeat there emboldened Twiston-Davies to think that his champion remained a legitimate challenger at 12, but he encountered a fresh setback.

"He's got a lung infection, so that's that," Twiston-Davies said. "What can you do? It's an absolute sickener, but they are very delicate creatures. I'm sure he's still as good as ever, he's been in great form, but you can't rush them. Hopefully he'll be OK for Liverpool."

For some trainers, it has been hard enough simply to decide between different races. But John Ferguson has finally settled on the County Hurdle, rather than the Champion Hurdle itself, for Cotton Mill; while Colin Tizzard has decided not to take on Sprinter Sacre in the Queen Mother Champion Chase, and will instead run Cue Card in the Ryanair Chase.

For punters, meanwhile, the next six days will be spent in an increasing frenzy. To certain diehards a race like the Gold Cup is willingly left to the purists. Instead they pore over handicaps like the Pertemps Final, and would nominate as their ultimate Festival darling a horse like Willie Wumpkins, who won the equivalent race three years running between 1979 and 1981.

All the buzz for next Thursday's renewal has been focused on Sam Winner – who looks well treated on his Triumph Hurdle fourth a couple of years ago. He made an eye-catching comeback from injury in a qualifier at Sandown in December, and Paul Nicholls immediately resolved to keep his powder dry for the final. In the meantime Sam Winner has enjoyed the bonus of a jumpers' bumper, at Kempton, where he beat no less a horse than Peddlers Cross. "He was really only half-ready at Sandown," Nicholls said. "I don't think we've seen the best of him yet over hurdles and three miles will bring out the best in him."

But Sam Winner is duly no better than 5-1 favourite – and Captain Sunshine looks better value, at four times those odds, after repeatedly catching the eye this winter. His trainer, Emma Lavelle, has endured a barren spell since saddling four winners on one Saturday before Christmas. But there have been signs of renewal of late and a Festival winner would redress all her frustrations since.

Lavelle says that Captain Sunshine has been dropping himself out on sticky ground before regrouping to finish well, but predicts that he will prove a different horse on a better surface.

Turf account

Chris McGrath's Nap

Sannibel (3.0 Lingfield) Did very well to close for second from off a steady pace last time; his best performance since changing stable.

Next best

Diplomatic (8.0 Kempton) Looked as good as ever when scoring over course and distance. Found drop in trip against him since.

One to watch

Living Leader (Nick Littmoden) Is lightly raced and shaped well in a sprint finish at Lingfield the other day, hitting top gear late.