Born in Neath, he began his professional career with Swansea City after joining the club from local non-league football at the age of 22.
He was known for having the longest throw-in in football, being able to regularly throw the ball over 30 metres and once held the world record with a distance of 44.6 m (48.8 yards).
He first joined Middlesbrough on trial, playing up front alongside Bernie Slaven for the club's reserve side.
He was instead offered a trial at Manchester City and played for the reserve side, again as a forward, before being asked to return at the start of the following season for pre-season training in order for manager Mel Machin to assess him.
[9] After returning from Manchester, Legg was offered a trial with his home town club Swansea City, playing in a reserve fixture against Cardiff City and, in August 1988, he was offered a professional contract by manager Terry Yorath, starting his professional career at the relatively late age of 22.
[6] A stress fracture of his leg meant he was forced to wait for his debut, eventually making his first appearance in a 2–0 defeat to Bristol City.
[10] During his time with Swansea, Legg's long throw-in ability gained significant attention and he was credited with a Guinness World Record in 1992 after taking part in a long throw competition arranged by the BBC television show Record Breakers held at Wembley Stadium in 1992 against Dave Challinor and Neil Thompson.
Originally signed by Barry Fry, he spent two years, winning his first cap for Wales on 24 April 1996 in a 2–0 defeat to Switzerland but was forced off after 30 minutes due to injury.
[16] In the final year of his contract during the 1997–98 season, Legg began negotiations over an extension but, after failing to agree terms, was dropped to the reserve side by manager Trevor Francis.
Just several weeks later manager Terry Bullivant was sacked and replaced by Tommy Burns who soon fell out with several players including Legg and Bowen.
With the 1999–2000 season coming to an end, Legg decided to play on for the remainder of the season, the only people aware of his condition at the club being manager Billy Ayre, physio Mike Davenport and club doctor Len Noakes, before having the tumour removed at the Princess of Wales Hospital in Bridgend in May 2000.
[22] After short spells playing for Newport County and Llanelli, Legg joined Conference North side Hucknall Town.