Welsh international Malcolm Allen spent two seasons at Carrow Road (1989-91) playing 46 times and scoring 15 goals. He was signed from Watford, his first professional club where he had progressed through the youth team ranks. He made his league debut in November 1985 at Upton Park and scored his first league goal against Arsenal the following Easter . Winning a call-up to the Welsh national squad for their May tour of Canada, he made his international debut and scored his first international goal. However he was unable to forge a regular spot in the Watford side and made just 39 league appearances scoring on five occasions.

In August 1988, Dave Stringer paid Watford £175,000 to bring Allen to Norwich. He gained further international honours for Wales but this nimble striker could not establish himself in the Norwich first team faced with competition from Robert Fleck, Robert Rosario, Alan Taylor and Henrik Mortensen. Primarily a substitute for Norwich, his moment of glory came when he struck four goals during Norwich's 8-0 FA Cup victory over non-leaguers Sutton United.

He was sold on to Millwall for £400,000 where he had his most prolific spell attracting the attention of Kevin Keegan who made him his first signing for Newcastle United (£250,000). A damaged knee plagued his time on Tyneside and he was forced to retire from playing professional football despite eight operations and the fitting of four screws. A last ditch effort by surgeons that involved pulling his tendon up through his knee cap to act as a substitute ligament appeared to work. He attempted to regain his fitness by playing alongside his brother Gavin for Aberystwyth Town in the League of Wales. However his family had trouble settling in Wales and returned to Hertfordshire. The Pink Un reported on Feb 23rd, 1997 that Malcolm had attempted to resurrect his playing career by joining Stevenage Borough of the Vauxhall Conference.

The Welwyn and Hatfield Times told on 17th December 1997 how Malcolm had joined Colney Health of the Herts Senior County League and that he had set up all three goals for his new side on his debut in a 3-3 draw with Wormley Rovers. Malcolm retains his links with Stevenage being employed as their Youth Team coach. His brother Gavin also joined Stevenage.

The December 1999 edition of Team Talk reported on developments at Rymans League minnows Molesey who appointed Malcolm Allen as Assistant Manager to new manager John Harding in an attempt to reverse their misfortunes. Allen has signed himself Rymans League forms and has used his Hertfordshire contacts to sign Ibrahim Oladeji from Bishop's Stortford, Matthew Potter and Phil Dean from Hitchin Town and Matt Corbould from Boreham Wood.

Malcolm left Molesey in the summer of 2000 to set up a coaching school in Wales and commentate for Welsh TV but an injury crisis saw him re-sign for Molesey in November 2000 until January 2001. He has also joined Letchworth to set up their Football Academy. Letchworth are managed by former England international Kerry Dixon. The Non League Paper reported on 18th March 2001 that Malcolm had joined Edgware as Player/Assistant Manager. He also worked for North Herts College setting up their Scheme of Academic and Football Excellence for 16-17 year olds.

Malcolm returned to Wales and to Aberystwyth in the summer of 2002 to head up Aberystwyth's youth development programme alongside his brother Gavin who still plays for the Park Avenue side. Malcolm's strong links with Hertfordshire football came in useful with Aberystwyth recruiting Paul Armstrong and Mark Duckett from Stevenage.

In the preparation for Norwich's FA Cup clash with Dagenham on 25th January 2003, the Pink Un interviewed Allen who had scored four goals in Norwich's 8-0 FA Cup victory over non-league Sutton in 1989. Allen was revealed as having returned to Stevenage as a youth coach. He is also involved in the EFCO schemes that take young players who fail to make the grade at big clubs and help find them future employment. He is also in demand as a football pundit, being one of a few ex-pros to speak fluent Welsh, thus gaining regular employment on TV and radio in Wales.

According to Mike Davidge's article in the Matchday programme for the clash with Crewe on 9th Augiust 2005, Malcolm is currently coaching Tottenham Hotspur's Under-15s.

On 9th April 2008, Allen was given a suspended jail sentence and a ban for drink-driving. Football pundit Malcolm Allen, 41, of Cranefield Drive, Watford admitted drinking up to 10 pints of beer when stopped by a Police Community Support Officer in Hertfordshire.At Stevenage Magistrates' Court he pleaded guilty to driving with excess alcohol and was given a four-week jail sentence suspended for two years.He was banned from driving for three years but opted to take a specialist court-appointed driver's course to cut the disqualification period to 27 months. Allen must also attend at least six sessions of an alcohol treatment course. Stevenage magistrates were told that he and his passenger were "paralytic".Prosecutor Charlotte Rind said both Allen and his passenger were seen coming out of a white van "looking drunk and staggering" after stopping off for a Chinese takeaway on 20 February. Allen failed a roadside breath test and was found to have 110mg of alcohol in 100 millilitres of breath when tested at a police station.

He told officers: "It could have been a lot worse and I'm glad that no-one was hurt. I have been a fool. I'm going to possibly lose my job and possibly my media work." Allen said he had not expected to drive and thought he would get a train back to Watford, the court heard.

In January 2010, he revealed in his biography the self-destructive and sometimes relentless binge-drinking which threatened to tear his life apart. The incredible catalogue of alcohol abuse and an unfortunate injury saw him reduced within a year from being a lauded professional flying high for Newcastle and Wales to cleaning an old people’s home and calling bingo numbers – a role which earned him the moniker “Mister Bingo Man”. Allen is now a presenter on S4C’s football show Sgorio and splits his time between Deiniolen and Watford