Big Buck's won under McCoy at Newbury in November
Big Buck's recorded his 10th straight success with victory at Newbury to give trainer Paul Nicholls his fourth win at Wednesday's fog-hit meeting.
AP McCoy rode the odds-on favourite to victory in the aptly-named AP Wins Sports Personality Long Walk Hurdle, beating 2007 winner Lough Derg.
Earlier, Champion Chase victor Big Zeb beat Golden Silver in the Paddy Power Dial-A-Bet Chase at Leopardstown.
And Hurricane Fly was made Champion Hurdle favourite after his win.
Big Zeb, who won the Queen Mother Champion Chase at Cheltenham in March, was claiming his fourth straight win for trainer Colm Murphy.
Barry Geraghty guided his mount to victory by one and three-quarter lengths from the runner-up, while Captain Cee Bee was last of the four runners.
Hurricane Fly beat Solwhit again after gaining the upper hand at Fairyhouse a fortnight ago to win the Festival Hurdle for Willie Mullins.
Mullins now has his sights set on the 2011 Champion Hurdle for his six-year-old, who has winning form at the Punchestown Festival but has yet to race at Cheltenham.
But perhaps the day belonged to Big Buck's after securing his 10th consecutive win. Former winner Lough Derg, with Tom Scudamore on board, led during much of the race before he was passed by the Nicholls horse in the final furlong.
Owner Andy Stewart said the dual World Hurdle winner, who has not lost since unseating his rider at the last fence in the 2008 Hennessy, will try to make it a hat-trick in 2011.
"I thought he (Nicholls) was mad to go over hurdles with him but on the basis he got that right, I'll always listen to him," reflected Stewart.
"In 2011 he will go for the Ladbrokes World Hurdle. He's the best horse I've owned."
Nicholls added: "He's getting more assured and is older and stronger.
"You can ride him any way you like now and he was probably a lot fitter from his last run.
"He'll probably run in the Cleeve Hurdle (Cheltenham, 29 January) now and then we'll go to Cheltenham and Aintree.
"Ability-wise, he's as good as I've trained - he's got it all."
Big Buck's was one of four winners for Nicholls, who also savoured success with Pride Of Dulcote, Ghizao and Rock on Ruby.
Pride of Dulcote beat Punchestowns to emerge as a Cheltenham Gold Cup contender.
AP Wins Sports Personality Long Walk Hurdle
1 Big Buck's (A P McCoy 2-13 fav)
2 Lough Derg (T Scudamore 40-1)
6 ran. Dist: 6 lengths, Head, 20 lengths
Winning trainer: Paul Nicholls
Paddy Power Dial-A-Bet Chase
1 Big Zeb (B J Geraghty, Evens fav)
2 Golden Silver (P Townend, 15-8 2nd-fav)
4 ran. Dist: 1¾ lengths; 1 length
Winning trainer: Colm A Murphy
1 Hurricane Fly (P Townend, 8-11 fav)
2 Solwhit (D N Russell, 6-4 2nd-fav)
5 ran. Dist: 2½ lengths; Short Head; 2½ lengths
Winning trainer: Willie Mullins