Martyn was born in Neath but went to school in Port Talbot and was well-travelled, having played in Switzerland, Germany and Belgium before coming to Maine Road for training when he was 15. City signed him up as a YTS trainee when he was 18 and he had was only a month into his first season with the club when he made his début for the reserves against Leeds, keeping a clean sheet. Martyn won 9 international caps for the Welsh Youth team and was also part of a useful City team at that level, getting a runners-up medal in the 1988/89 FA Youth Cup after a close final against Watford. The following season he was the hero in the Lancashire FA Youth Cup final victory over Preston when he saved two spot-kicks after the match at Deepdale had gone to a penalty shoot-out. The City side also included Garry Flitcroft, Michael Hughes and Mike Sheron.
Under the managership of Mel Machin, Martyn had been Andy Dibble's understudy but when Howard Kendall took over and brought in Tony Coton, Martyn was back to playing for the A-team. He wasn't forgotten though and on 10th October 1990 he played his first game for the first team as a second-half substitute in the League Cup 2nd Round 2nd Leg match against Torquay United. City were 4-0 up from the first leg and Kendall had planned to give him a run-out for the second half provided City hadn't conceded any goals (this was before separate goalkeeping substitutes were introduced). The game ended 0-0, which was disappointing for most of the City fans at the game but a precious clean sheet and good experience for Margetson. Later that season, Kendall left for Everton and was replaced by Peter Reid. It wasn't long before Margetson overtook his fellow countryman Dibble in the goalies' pecking order, becoming City's regular reserve-team 'keeper.
Martyn's full League début came in the penultimate game of the season, a Manchester derby at Old Trafford. Tony Coton had been sent off against Derby County two games earlier and was serving a three-match suspension. The youngster played well and would count himself unlucky to have been beaten by Colin Hendry's attempted clearance, which sliced into the City net for the only goal of the game. Another big game was to follow as Sunderland came to Maine Road looking for a win to keep them in the top flight, accompanied by over 10,000 supporters. City won a thrilling game 3-2. Margetson also played with the first team in Hong Kong during the summer whilst Coton was away with the England squad. The final game of Coton's suspension was the opening game of the 1991/92 season at Highfield Road. Martyn kept a clean sheet and City beat Coventry 1-0. Three more first-team appearances followed that season, two in the League and one in Colin Hendry's last game for City, a 3-2 defeat at Hillsborough in the Zenith Data Systems Cup.
Tony Coton played in all but 2 matches in the 1992/93 season and Andy Dibble was preferred for one of the other two, so Martyn's first appearance of the season had to wait until City's last, a home game against Everton. It was a nightmare for the youngster as Everton blitzed City with three first-half goals, two of them from mistakes by Margetson. The crowd made their feelings plain and Andy Dibble took his place for the second half to save him from further embarrassment. The final score was 5-2. "I learnt a lot from that game", said Margetson. "It was the lowest point of my career but everything prior to that had gone so well for me. I'd had several first team matches for City and they'd all gone really well. But the Everton game brought me down to earth with a bump and showed me the reality of the professional game. It made me realise that it wouldn't always be a bed of roses. It was the kind of situation that would have wrecked some people. But I was determined it wouldn't affect me long-term and the backroom staff at the club rallied round to buck me up. They never let my head drop. They told me not to forget the fact that even the very best goalkeepers have bad games. I have never forgotten those words. I didn't let it destroy me and I've forgotten it now; I just hope I'm not remembered for that game."
Tony Coton and Andy Dibble were the only first-team goalkeepers used in the 1993/94 season, though Margetson was an unused substitute on a number of occasions. However, he spent a month at 2nd Division Bristol Rovers on loan in December, making his début against his childhood favourites Swansea City. There was another loan spell in spring, this time to high-flying Bolton Wanderers but Martyn didn't get to play as the two reserve matches he was scheduled to play in were snowed off and he was then recalled to Maine Road to take Andy Dibble's place on the bench after Tony Coton picked up a knee injury. As a result of a combination of injuries and suspensions, City used four goalkeepers in the first team in the 1994/95 season but Martyn wasn't one of them! He did make it as far as the bench on a number of occasions though. On transfer deadline day he went out on loan to Luton Town but was recalled again when both Tony Coton and Andy Dibble picked up injuries. Veteran John Burridge was the man keeping him out this time. With the change of management at the club at the end of the season, maybe Martyn's luck will change soon.
Manager Joe Royle faced a difficult task after the 1997/98 season. He had to trim a squad which consisted of more than 30 professionals. Surprisingly Martyn was one of the boys facing the axe, and put on a free transfer.
Martyn must be worried that 43-year old veteran John Burridge kept him out of the side at the end of last season; one or more loan spells at Endsleigh League clubs would help him to gain confidence and get some valuable experience. Hopefully he'll come good and erase the memory of that fateful game against Everton.
Svenn Hanssen, Paul Howarth, Adam Houghton, Patrick Bedell, Dan Rigby, David Lamb