Topacio overcame connections worries about the drying ground to land the featured IAWS Champion 4YO Hurdle in front of another large crowd.
Charlie Swan had the gelding prominent throughout, and drew clear at the home turn to beat Lord Brex by 2 1/2L.
'I would'nt have run him only they watered the course yesterday evening,' said trainer Pat Hughes.
Hughes added: 'He will have a break now, and may come back in the autumn for a staying handicap on the Flat.'
Nicky Henderson and Mick Fitzgerald combined for their second Grade 1 win this week when Tiutchev took a thrilling 2m Novice Chase.
The Arkle Chase hero and Frozen Groom were in the air together at the final three fences, with Tiutchev staying on much better from the last to score by 6L.
The Champion Stayers Hurdle also went to Britain with Rubhahunish benefitting from a forceful ride by Carl Llewellyn.
The 9yo made most of the running, and stayed on strongly from two out to beat Effectual by 7L.
'The change in tactics suited him, and hopefully he will go for the Stayers at Cheltenham next year,' said winning trainer Nigel Twiston-Davies.
Risk Of Thunder made Irish racing history when taking the La Touche Cup for the sixth successive year, making all for a runaway victory under Ken Whelan.
Whelan had his head shaved last weekend to raise #5,000 in aid of handicapped children.
Winning trainer Enda Bolger outlined plans for the remarkable stayer afterwards.
He said: 'He will probably go next for the Marlborough Cup (May 28), and there is another similar race after that at Creon in France.'
Michael O'Brien has the Galway Plate as the summer target for Dovaly who made all under Tom Rudd to take the Pat Taaffe Handicap Chase.
'If you spit on the ground he can't handle it,' said O'Brien, who added: 'He's a great jumper, and stays well.'
Ruby Walsh consolidated his position as the leading rider at the meeting when partnering his fourth winner aboard Killultagh Storm in the 2m handicap hurdle.
The 6yo quickened under pressure, heading Winter Garden after the last to score by 1 1/2L.
'He will go next for the Murphys Handicap Hurdle at Killarney, and I am looking forward to him going over fences next season,' said trainer Willie Mullins.
Philip Hobbs blundered his second win at the meeting when Wave Rock led four out in the 2 1/4m novice chase, while Forever After edged out Surprising in the bumper.
The Tote aggregate of #640,447 (up #112,000 on last year) was a new course record.
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