In 1994 Moonax became the first horse to win both the Classic St Leger and the Prix Royal-Oak and was named European Champion Stayer.

Moonax, a chestnut horse with a white blaze who stood 16.2 hands high,[2] was bred in Ireland by the Liscannor Stud.

[4] Moonax was sent by the County Limerick-based[5] Newborough Stud as a yearling to the Goffs sales in October 1992, where he was bought for IR£37,000 by the Curragh Bloodstock Agency[6] He entered the ownership of Sheikh Mohammed and was sent into training with Barry Hills at Lambourn.

[13] The Chester form was let down when Broadway Flyer finished well down the field in the Derby and Moonax was a 14/1 outsider when he was sent to Royal Ascot for the King Edward VII Stakes.

In July he made no show when unplaced in the Deutsches Derby and when dropped down in class for a minor race at Newbury in August he could finish only third after leading briefly in the straight.

This was part of a tactical plan by Hills, who felt that the early pace would be very strong, and that Moonax's best opportunity would be to wait for the others to tire before making his challenge.

Plans for Moonax to join Sheikh Mohammeds's Godolphin team were modified, and he stayed under Hills' care for the rest of his career.

Moonax tracked the leaders before taking the lead in the straight and ran on strongly to win his third successive race, this time by one and a quarter lengths.

[22] Greg Wood writing in The Independent, praised the colt's "authority", "strength" and "enthusiasm" and predicted that he would be hard to beat in the year's top staying events.

[23] The race also helped to give Moonax a reputation for unpredictable behaviour: he turned his head and attempted to bite Always Earnest in the closing stages.

He reappeared in a minor stakes race at Haydock in late September and recorded his first win for well over a year when defeating the Gran Premio del Jockey Club winner Court of Honour by a length.

[25] Before the Prix du Cadran at Longchamp in October Moonax behaved poorly, bucking violently and almost unseating his rider Frankie Dettori.

[1] A second attempt at the Prix Royal-Oak ended in disappointment: he led for most of the race and defeated both Nononito and Always Earnest but was caught in the closing stages and beaten half a length by the mare Red Roses Story.

Those plans were modified after he was beaten at odds-on on his National Hunt debut, finishing second to Sharpical at Huntingdon in December[28] although other races at the Cheltenham Festival were still being considered.

[28] Moonax's hurdling career continued with a third place behind Sanmartino at Leicester, but the experiment was abandoned after he behaved in an "unruly" manner before finishing unplaced at Ludlow a month later.

[34] Moonax stood at the Clongeel Stud, near Mallow, County Cork,[35] Ireland, where he was mainly used as a sire of National Hunt horses.