The seven-year-old broke a blood vessel on Saturday in the Game Spirit Chase at Newbury as Kalashnikov finished last in a field of five, with Altior claiming the win.
Trainer Amy Murphy says Kalashnikov will undergo tests and she admits his season may well be over, but she hasn’t ruled out the Aintree Festival just yet.
Kalashnikov won the Devenish Manifesto Novices’ Chase at the Merseyside track last year and the Melling Chase is likely to be the target in April if the Grade One-winning chaser is able to feature again before the season ends.
She said: ‘He’s just going to need a bit of time off now.
He’s bled twice in a short space of time, and realistically Cheltenham is going to be off the cards.
‘ She added: ‘He’s going to go into Newmarket Equine Hospital on Monday morning and have a full MOT, just to check there’s nothing underlying that’s causing him to do it.
‘I suppose by the end of next week we’ll either have found something or found nothing – and it’ll just be a case of time’s a great healer.
‘I don’t want to write off Aintree, then suddenly we find something next week, we get it fixed – or it’s something simple, like his wind.
‘So I don’t want to write off the whole season, then be in a different place in six weeks’ time.’
Contingencies to re-stage if Cheltenham were postponed ‘for any reason’.
Doncaster and Newbury options for Towton faller.
Trainer took a batch of 13 horses to work on Tuesday morning.