Master Minded is beatable. That's the message from Colm Murphy as he finalises Big Zeb's preparations for next Wednesday's Queen Mother Champion Chase at Cheltenham.

Paul Nicholls' stable star is an odds-on favourite to become the first horse since Badsworth Boy to win the Grade One two-mile chase three times.

Master Minded hung badly right in defeat on his last visit to Cheltenham and connections subsequently discovered he had cracked a rib. He returned after a three-month lay-off to record an impressive victory in the Game Spirit Chase at Newbury but Big Zeb's trainer believes Master Minded is vulnerable.

Murphy said: "For the past two years, he's gone there and looked invincible and he's been unbeatable but I don't think that's the case this time. It depends on which Master Minded turns up but there are some good horses up against him."

Big Zeb fell in the Champion Chase last year and flopped on his only other appearance in Britain, when very soft ground saw him bogged down in Sandown's Tingle Creek Chase in December.

Last seen winning the Grade 2 Tied Cottage Chase at the end of January and still available at 9-1 with William Hill, Big Zeb can mix it with the best, according to Wexford-based Murphy.

"We are a lot wiser going to Cheltenham this year than we were last year. We're not there to make up the numbers," he said.