The most exciting new recruit to British steeplechasing makes his debut at Sandown tomorrow but the best of the previous generation must miss his eagerly awaited return. Just as Emma Lavelle was confirming plans for the graduation of Crack Away Jack, Ferdy Murphy was forlornly ruling Kalahari King out of his intended run at Kelso.

Kalahari King lost out by a mere short head to the Irish-trained Forpadydeplasterer in the Arkle Trophy at Cheltenham and is one of few horses that could feasibly prevent Master Minded completing a Champion Chase hat-trick. He will miss an early duel in the Tingle Creek Chase next month after an irritating setback.

Murphy, his trainer, explained: “He suffered an overreach two days ago and it blew up last night. He's needed antibiotics to clear the infection and that means he can't run in what was a perfect race at Kelso. It's a kick in the teeth. We couldn't go to the Tingle Creek without a run, so he'll be aimed at the Peterborough Chase now.”

Crack Away Jack is already contesting favouritism for the Arkle next March. Lavelle, while not entirely discounting another bid for the Champion Hurdle, in which her charge was fourth last season, is confident he is ready for fences but admits her nerves will be frayed tomorrow.

“Crack Away looks fantastic and I'm happy to start him off at Sandown, where I think he'll cope with the test of jumping,” she said. “There are some nice two-mile novice races there through the season and we'd be looking at the Henry VIII next month if all goes well on Saturday.”

Lavelle says she has “filled every nook and cranny” of her Hampshire yard with boxes and she now trains a 70-strong team. Kangaroo Court, who has won both his chases in taking style, will step up to graded company in the Rising Stars Novices' Chase at Wincanton tomorrow, “so long as the ground does not get too soft”.

A fine card at Wincanton is also set to attract Celestial Halo, runner-up to Punjabi in the Champion Hurdle. Paul Nicholls, his trainer, said yesterday: “The rain they have had makes the Elite Hurdle attractive. We have the Greatwood at Cheltenham as an option but it's likely he'll run at Wincanton.”

Ruby Walsh, who has been sidelined by a foot injury since last weekend, returns at Down Royal today and will partner all Nicholls's runners at Wincanton.