After falling on his chasing debut at Newbury in November, the six-year-old showed he has heart to match his giant frame when building on an encouraging outing in last month's Lanzarote Hurdle at Kempton with a length-and-a-half success in the Grade Three event.
Nicholls said of the 11-2 winner: "He needed the run the other day in lots of ways to sharpen him up. We always fancied him today. I was slightly concerned about the ground being as soft as it was, but he kept galloping. What he does now is irrelevant as he has won a £100,000 race and he will be chasing next season. He is the future."
While the 10-times champion trainer has no immediate plans for Topofthegame, he hopes he can develop into a Grand National contender in the future.
He added: "I said to Paul Barber (part-owner) he is bigger than Denman ever was. He stands at 17.2 hands plus.
"Waiting to go chasing next year will be the best thing that has happened to him. He stays forever and he is the sort of horse that might end up in a Grand National. To be honest, if he didn't run again (this season) it wouldn't matter."
Gino Trail (4-1) may be entering the veteran stage of his career but he showed he still retains plenty of enthusiasm when holding Dolos at bay in the Betfred "Treble Odds On Lucky 15's" Handicap Chase.
Winning trainer Kerry Lee said: "He is such an enthusiastic horse for an 11-year-old. He has been enjoying himself at home this week roaring around the woods and he went for a splash in the river yesterday. He is really loving life.
"He had to dig very deep and that is probably his limit today. He got beaten by Speredek last time and he has gone on and run so well at Ascot in top-grade company. He has come out and franked that form. He will have an entry in the Grand Annual, but he needs soft ground."
Charlie Longsdon had nothing but praise for Ben Halsall, son of winning owner Alan, after Ballydine (4-1) put more experienced rivals in their place on just his third start over fences when getting up in the Betfred Mobile Masters Handicap Chase.
Longsdon said: "It was a brave shout by Ben. He said we have got to go for it, but I said he was too inexperienced to go for it on his third run over fences.
"That (National Hunt Chase) could well be a possible route. It will be very much a thought for us now. All he does is stay and he could be a nice ride for the four-miler."
Nicky Henderson supplemented the gains of Terrefort in the Scilly Isles Novices' Chase and Buveur D'Air in the Contenders Hurdle with Countister in the Betfred "Home Of Goals Galore" Novices Hurdle.
The 5-6 favourite - who was initiating a double for Buveur D'Air's rider Barry Geraghty - is set to head for the Trull House Stud Mares Novices' Hurdle at the Festival next month.
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