Mus-If was a bay horse bred in the United Kingdom by Eurostrait Ltd. As a yearling he was consigned to the sales at Deauville in August 1997 and was bought for ₣350,000 by Hamdan Al-Maktoum's Shadwell Estate company.
[6] The colt was moved up in class for the Listed Tyros Stakes over the same course and distance on 15 August for which he started favourite but was beaten into second place by the Jim Bolger-trained filly Arctic Blue.
He found another Bolger filly, St Clair Ridge, too good for him in the Group 3 Futurity Stakes two weeks later and was beaten a length and a half into second place.
Wearing blinkers, Mus-If went to the front from the start, opened up a clear advantage approaching the last quarter mile and held off the late challenge of Coliseum to win by a neck.
After winning a similar event at Keeneland Racecourse in April he was stepped up in class to contest the Henry S. Clark Stakes over one mile at Pimlico Race Course on 4 May.
[14] The gelding's winning streak came to an end in June when he was beaten into second place by Del Mar Show in the Grade III New Hampshire Sweepstakes Handicap at Rockingham Park.
In the late summer and autumn of 2002 Mus-If was campaigned at Delaware Park Racetrack where he finished sixth in the Sussex Handicap and third in the Leader of the Band Stakes before winning a claiming race on 6 October.