Lexi's Boy put up a game performance in testing conditions when making all the running in the bet365 Josh Gifford Juvenile Handicap Hurdle at Sandown.
Trainer Donald McCain registered his 150th success of the campaign on Friday and Lexi's Boy (9-1) ensure the Cholmondeley handler began the final day with a winner.
Jason Maguire felt the best place to be was in front and he dictated matters. Though he set just a sensible pace, not many horses got into the race as the grey completed a hat-trick in meritorious fashion.
He stuck on dourly up the hill to win by three and three-quarter lengths from Sadler's Risk with Ulck Du Lin staying on for third place.
Maguire said: "It's been a great season and great to ride for such a good yard. They are tough horses and Donald's done a fantastic job.
"This horse got turned over a couple of times up north so we thought we'd change tactics at Ascot and make the running.
"It was the same again the other day at Ayr and he won well. Today on heavy ground he's really ground it out and I think there's more to come from him."Carrying a big weight on heavy ground held no fears for Gibb River (11-1), who finally opened his account for the season in the bet365 Handicap Hurdle.
The Nicky Henderson-trained six-year-old was never far off the pace and wore down long-time leader Arab League on the run home from the final flight.
Answering 5lb claimer Jeremiah McGrath's every call, Gibb River landed the spoils by half a length from Arab League with Act Of Kalanisi two lengths away in third and Big Easy a head back in fourth.
The Stuart Kittow-trained Weapon Of Choice (15-8 joint-favourite) rallied well for Tom Queally to deny Sam Sharp by half a length in the Poker At bet365.com Handicap.
Aidan Coleman stole the show on John Berry's Silken Thoughts (8-1) in the Casino At bet365.com Flat V Jump Jockeys Handicap.