A look ahead to Betfair Ascot Chase Sam Twiston-Davies feels connections will learn an awful lot about smart novice Ptit Zig in Saturday's Betfair Ascot Chase. Unbeaten over fences, last year's Champion Hurdle sixth is a late replacement in the Grade One for injured stablemate Al Ferof. Paul Nicholls' six-year-old is favourite against some more experienced rivals after rattling off four quick wins this term. Twiston-Davies has been in the saddle for all for of his victories this term and was impressed by the turn of foot he showed to beat the useful Champagne West in the Dipper Novices' Chase at Cheltenham on New Year's Day. "I'm looking forward to it. We'll learn a bit more about him as he's stepping up in grade and taking on some good opponents, but that's why we'll learn a lot and hopefully he can run a big race," Twiston-Davies told At The Races. "From his first win at Exeter he has kept progressing, he's got better and better every time and when we beat Champagne West last time, I was very happy with him. "He'd had a few quick races then, but he's been freshened up and hopefully he goes there in good order. "Hopefully the ground will be decent as that is what he wants - at Cheltenham last time he didn't travel as well as he can. The trip is no problem and Paul has talked about him being hopefully a King George horse." Just behind Ptit Zig in the betting is Alan King's Balder Succes. One of the leading novices over two miles last season, he skipped the Arkle to wait for Aintree and it paid off as he claimed Grade One glory. This year he was coming up just short against the best two-milers and King stepped him up in trip last time at Kempton, which seemed to suit. "Balder Succes seems in very good form. Ascot has been the target since Kempton and everything has gone well," said King. "He had a little school the other morning and we are very happy with him. I am looking forward to running him, but it is going to be a very good race and I have a lot of respect for the other five. "I think the slight step up in trip will be OK. He wasn't stopping at Kempton and he won over two and a half around Chepstow a couple of years ago. "A lot of these good juveniles need a bit further as they get older. We'll get Saturday out of the way before we start thinking of Cheltenham." The rank outsider is Colin Tizzard's Theatre Guide, who shaped well for a long way on his first start for some time in the BetBright Cup at Cheltenham. He finished third in the Hennessy as a six-year-old and Tizzard has always rated him highly. "He came there between the final two fences at Cheltenham and we thought he had a chance. His run petered out a bit and whether he blew up or just wasn't good enough, I don't know," said Tizzard. "He seems in really good form. He has definitely got something about him and one day - given any luck at all - he is going to shake them up in a big race. Let's hope Saturday is the day. "He has plenty of pace and the race won't be run at a dawdle anyway, so that will bring stamina into play as well. We have left him in the Cheltenham Gold Cup. He is not at that level yet but Saturday will tell us more."