Champion jumper Wells headlines a field of nine for the Crisp Steeplechase at Sandown while a field of 11 has been declared for the Grand National Hurdle.
Sunday's meeting at Sandown is highlighted by the two jumps features, with 12-year-old Wells striving to win the Crisp (4200m) for a second time.
He won in 2017 on his way towards winning a fourth Grand National Steeplechase later this month.
Wells's previous Grand National Steeple wins came in 2014, 2016 and 2017 while he lost his rider in last year's race.
Wells won the Mosstrooper Steeplechase at Pakenham in his first jumps appearance of the year on July 21 and is the $2.70 favourite in an early market for Sunday's race.
The veteran will carry top weight of 70kg under the set weights plus penalties conditions.
The Patrick Payne-trained Killarney Kid, winner of the Kevin Lafferty Hurdle at Warrnambool two starts ago, is the top weight with 69kg in the $250,000 Grand National Hurdle.
Killarney Kid is on the second line of early betting at $3.80 behind New Zealander Gobstopper ($3.50) who won the Brendan Drechsler Hurdle at Pakenham in his first Australian jumps start on July 21.
The meeting comprises three jumps races and seven on the Flat.