The champion trainer has saddled a record nine previous winners of the Grade One contest, with Alexander Banquet (1998), Hurricane Fly (2008) and Nichols Canyon (2014) among them.
In Marine Nationale, however, Connell has a potential star of his own, with bumper wins at Punchestown and Killarney supplemented by a clear-cut success on his hurdling debut at Punchestown in October.
"He's in good form, he worked on Wednesday and we're expecting a big run," said Connell.
"We're well used to taking Willie Mullins on! We're taking him on in Ireland every day and the competition is stiff.
"But we couldn't have our horse in better condition, we're happy and going there optimistic."
In the aftermath of Marine Nationale's most recent success, Connell raised the possibility of giving his charge another run before stepping up to the highest level, but ultimately decided against it.
He added: "The only reason to give him another run was if I thought he needed the experience jumping-wise, but his jumping was so good in Punchestown the first day and he had been prepared for a point-to-point career, so he had plenty of that done at an early age.
"I didn't feel the need to run him again. We're going there fresh and the break has done him good."
Champ Kiely appears the Mullins first string under stable jockey Paul Townend off the back of an impressive Grade Three success at Tipperary on his latest start.
Hercule Du Seuil is also a Grade Three winner, having claimed Navan's For Auction Novice Hurdle, while Polo Lounge and Ashroe Diamond – the only mare in the field and the mount of the trainer's son Patrick – are both one from one over obstacles.
Mullins junior said: "Champ Kiely has surprised us, which is great. He showed good stamina to win over two-mile-five in Galway with a stiff uphill finish, and showed good speed to win on a flat track like Tipperary over two miles.
"He's got a lot of versatility, is hard fit having been on the go during the summer and he has experience, so he looks the one to beat.
"We've had good luck in this race with fillies, winning it last year with Statuaire and Airlie Beach (in 2016), and Ashroe Diamond is a high-class mare.
"She won the Grade Two bumper in Aintree last season and has had a run over hurdles. I think she'll come forward from that and she has to have a huge chance.
"Hercule Du Seuil is hard fit and has experience, but probably needs to step up on his Navan run, and Polo Lounge is improving all the time, but would need a career-best to get involved."
Irish Point (Gordon Elliott), Path D'oroux (Gavin Cromwell) and Prairie Dancer (Joseph O'Brien) are the other hopefuls.