Frodon is likely to be aimed at the Cheltenham Gold Cup after returning to winning form under Bryony Frost.
The 9-2 shot, trained by Paul Nicholls, led from start to finish and jumped superbly to win the Matchbook Handicap Chase despite carrying top weight.
It was a sixth victory at the track for the horse, who helped Frost create history last year.
Victory in the 2019 Ryanair Chase was the first over fences at the Cheltenham Festival for a female jockey.
"I'm not going to say he will win the Gold Cup, but he always runs well around here and he deserves his place in it," said Nicholls.
Meanwhile, Mac Swiney won the Vertem Futurity Trophy at Doncaster in wet conditions.
In the final big race of the season for juveniles, trainer Jim Bolger's runner struck late to overhaul leader Baradar, who finished third.
Pre-race favourite One Ruler came in second by three-quarters of a length, after a tenacious Mac Swiney held him off in the final furlong.
The winner at Town Moor often goes on to contend the Classic races the following year.
Recent winners that have gone on to land Classics include Camelot, Kingston Hill and Kameko.
Mac Swiney, a Group Two winner on soft ground at the Curragh in August, had since managed only eighth of 10 horses on the same course and distance in the National Stakes.
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