"I try to protect him now and just really aim for the classes that matter," said Tiffany of the 15-year-old gelding winning the final grand prix of the season at Tbird.

The Canadian rider steps up from a win in the U25 last week to record her first senior FEI victory in the $36,900 CSI2* 1.45m class.

Vanessa Mannix (CAN) finished second with Balzane du Mazes, while Brennan's fiancée Lauren Crooks (USA) finished third.

A previous series winner, she reclaimed the title with Havana, a horse she has developed herself since the mare was four years old.

The pair lead wire-to-wire in the $15,000 CSI4*-W 1.45m at Thunderbird Show Park's Harvest Celebration over Justin Prather and EZ Ace.

The prolific winner places one-two in Friday's $75,000 CSI4*-W during the Harvest Celebration; his student Vanessa Mannix (CAN) claims 3rd.

It came down to a two-horse race between Hannah Rajotte/ Patronus and Ashley Arnoldt/Lestat OLD over Peter Holmes' course at tbird.

A contentious eight-horse jump-off saw Vanessa Mannix (CAN) and Catinka 25 settle for second with Conor Swail (IRL) and Theo 160 third.

The newlywed won the $15,000 CSI3* Maui Jim Winning Round 1.45m aboard her longtime mount, Goodwill VB.

In the four-horse jump-off in the 1.50m CSI3* class on Thursday, the Irishman stacked the odds by making up 50 per cent of the lineup.