Sizing Europe and Big Zeb are among 10 horses left in the Queen Mother Champion Chase.
The respective 2011 and 2010 winners are among 10 horses left in the two-mile feature at the confirmation stage.
Sizing Europe defeated Big Zeb by five lengths 12 months ago to follow up his win in the Arkle Trophy in 2010.
And Henry de Bromhead's stable star got the better of his old rival by 15 lengths in the Tied Cottage Chase at Punchestown last month.
However, Colm Murphy is expecting a better performance from Big Zeb next week.
Willie Mullins has left in the progressive Blazing Tempo, who completed a hat-trick of victories at Fairyhouse, while the Noel Meade-trained Realt Dubh, third in last year's Arkle Trophy, is the other Irish possible.
Heading the home brigade is the Nicky Henderson-trained Finian's Rainbow, who chased home Captain Chris in last year's Arkle.
He was caught close to the finish by Somersby in the Victor Chandler Chase at Ascot last time.
Somersby is, however, more likely to take his chance in the Ryanair Chase on Thursday, unless there is plenty of cut in the ground.
Others standing their ground are Wishfull Thinking, Gauvain, Kauto Stone and I'm So Lucky.
The withdrawn horses were I'msingingtheblues, Jewson Novices' Chase-bound Peddlers Cross, Nacarat and Hold Fast.
Noel Meade has still to decide whether Realt Dubh, who has yet to run this season, goes in the Queen Mother or the Ryanair over five furlongs further.
"Realt Dubh is currently 50-50 to run in either the Queen Mother Champion Chase or the Ryanair Chase. I am not sure yet, but we think he is in great shape and he seems well. We have been really pleased with his work - he worked at Navan on Monday and we were very happy with him," said Meade.
"He had a bit of a setback before Christmas, which took him some time to get over and it held us up so we haven't had time to run him.
"We have often wondered if he would get the full two miles and five furlongs around Cheltenham, hence why he is in the Queen Mother Champion Chase as well. We are still very much open minded about it and it would also depend on what is going to run in both races.
"I think better ground suits him better. He is a very decent horse - he won three Grade Ones last season so he is a good horse."