Became the country's first £1million goalkeeper in joining Crystal Palace from Bristol Rovers in 1989, having made over 100 appearances for the West Country club.
Leeds paid £2.25million for him in the summer of 1996 - then a record for a goalkeeper. He had a superb first season for the Whites as part of George Graham's Leeds revolution.
His form has continued to be a model of consistency and he was an ever-present in the 1999/2000 Leeds campaign. He helped United to third place in the Premiership, a place in the Champions League and the semi-finals of the UEFA Cup.
Part of the ill-fated Euro 2000 squad and was guilty of a serious error in the vital group-closer with Romania. Had established himself as the England No.2 goalkeeper and looked set to take over from David Seaman whose form had slipped.
However, with a wealth of young goalkeepers emerging, including Leeds team-mate Paul Robinson, Martyn must try to establish himself in the England set-up once more.
In his first game in charge England boss Sven Goran Eriksson gave Martyn the second-half of the friendly against Spain and he impressed again in the next friendly against Mexico.
Is still unable to claim a regular starting place in England's competitive matches but many people, including England's 1966 World Cup winning keeper Gordon Banks, believes he should be given the gloves.
But Seaman is firmly entrenched as Sven's number one - barring, of course, injury problems. Martyn did get to start England's 2-2 draw at home to Greece in the final qualifier for the 2002 World Cup.
And he made a vital save from Karangounis as the score stood at 1-0 to the Greeks. England promptly equalised and Martyn was one of a small band of heroes that day at Old Trafford.
Was an ever present in the 2001/02 campaign with Leeds and was again Seaman's understudy at the 2002 World Cup, and did not get to see any of the action.
His decision not to go on the club's tour of Australia and the Far East handed Robinson the chance to take the goalkeeping jersey. He had impressed greatly during the 2001/02 campaign, and Martyn will have to stay on his toes to remain number one under new boss Terry Venables.
By the start of the 2002/03 campaign, Martyn had played 273 games for Leeds. He has a contract that runs out in the summer of 2004, by which time he will be approaching the age of 38.