A lung infection means Imperial Commander has once again been denied the chance to bid for more glory in the Betfred Gold Cup at Cheltenham.
Trainer Nigel Twiston-Davies was convinced the 12-year-old was back in the same sort of form which saw him defeat Denman and Kauto Star in the 2010 renewal.
Having pulled up with a broken blood vessel the following year he missed a whole season but came back at Cheltenham in January with a fine run when only narrowly denied by Cape Tribulation in the Argento Chase.
"It's an absolute sickener but they are very delicate creatures." - Twiston-Davies
Twiston-Davies said: "He's got a lung infection so he won't be going to Cheltenham, that's that.
"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."