Saphir Du Rheu is to undergo a breathing operation today following his lacklustre effort in the Long Walk Hurdle at Ascot.

Leading John Smith’s Grand National contender Tidal Bay has suffered a “tiny stress fracture” and will not run at Aintree on April 6.

Paul Nicholls believes he is “nearly there” in his battle to get Kauto Star fit for Friday’s Betfred Cheltenham Gold Cup.