NUBE Negra (7/1) can cause a minor surprise in the Betway Queen Mother Champion Chase, today's feature race at the Cheltenham Festival. Backing against Chacun Pour Soi (10/11) may prove folly, of course, but as yet the big-race favourite still needs to prove his appetite for the Cheltenham hill. While Willie Mullins' hotpot has been beaten just once in Ireland since his move from France in 2016, in all that time we have only seen him in action seven times. Nevertheless, as a nine-year-old he should be at his peak now - although there is obviously a fragility about him, which reared its head 12 months ago when he was ruled out on the morning of the race.