Ben Maher wins the Christmas Cracker at Olympia

Olympic gold medallist Ben Maher won the Christmas Cracker in dramatic fashion on the second day of the London International Horse Show's showjumping at Olympia.

Riding eight-year-old prospect Aristo Z, he triumphed in a 15-horse jump-off.

Maher's London 2012 medal-winning colleagues Scott Brash and Peter Charles were not far behind, finishing fourth and fifth

Maher said of Aristo Z: "He is a crazy horse, not conventional."

"He's difficult to ride, but also such fun because he always gives 100%. He can jump anything."

Frenchman Roger Yves Bost looked to have done enough for victory aboard Castle Forbes Myrtille Paulois when clocking 34.49 seconds to take charge of the jump-off.

But Maher capitalised on being drawn last to go by clipping 74 hundredths of a second off Bost's time to clinch the £5,300 prize.

Maher is also attempting to win the Rolex FEI World Cup for a second successive year on Saturday, riding his London 2012 horse Tripple X III.

The 29-year-old has also made a strong opening in his bid to become the leading rider of the show again, having collected the prize last year.

It is presented to the most successful rider across 13 of the London International's premier classes, and Maher currently sits top of the leading rider category after going on to post a third-place finish in The Mistletoe Stakes speed class.

Riding Milena, Maher clocked 50.29 seconds following another strong performance.

Essex-based Laura Renwick was second on Roller Coaster with Switzerland's former world number one Pius Schwizer winning by a comfortable margin of 1.38 seconds aboard Ulysee.

Maher is now five points clear of Renwick in the leading rider race, while Bost and Italian Luca Maria Moneta have also moved above Brash, who has dropped to fifth.

Maher took his day's earnings past £10,000 by capturing the Alltech Christmas Puissance title.

Maher and Noctambule Courcelle were the only combination to make a fourth jump-off, with the puissance wall raised to 7ft 1in.

Although they nudged a brick out of it they still finished first as his closest challenger, Renwick, had already withdrawn on Roller Coaster.

The puissance does not count towards the leading rider award.