Manchester United manager Sir Alex Ferguson paid tribute to the "potential and promise" of 21-year-old striker Jimmy Davis, who died in a car crash today.

Davis was killed in an accident on the M40 this morning on his way to make his league debut for Watford, for whom he was about to begin a year's loan spell.

Watford postponed their home clash with Coventry as a mark of respect to the player and Ferguson led the tributes to Davis.

He said: "You could not meet a nicer and more bubbly character than Jimmy Davis.

"He was a player with real potential, that's why we sent him to Watford this season. At 21 he had great promise. We are all really sad. It's terrible news."

A further statement from United read: "Everyone at Manchester United is devastated to hear about Jimmy's tragic death. We send our sincere condolences to his family and many friends. He will be sadly missed."

Davis went out on loan to Swindon last season, making 15 appearances for the Second Division club and scoring three goals.

He made his solitary appearance for the Red Devils in a Worthington Cup defeat to Arsenal on November 5, 2001.

Following his loan spell at Swindon, he returned to Old Trafford and was on the bench for the Champions League clash away to Deportivo La Coruna in March.

He signed professional forms with United in July 1999 and was capped by England at Under-20 level.

The accident on the M40 happened in the early hours of the morning in Oxfordshire.

The footballer's grey BMW 3-series was in collision with a DAF lorry as both vehicles were travelling southbound just before 5am.

Davis was pronounced dead at the scene and two lanes of the carriageway were closed while investigators examined the scene.

At 12.20pm Hertfordshire police issued a statement confirming Watford's fixture had been cancelled and advised fans who had already started their journey to turn back.

The driver of the lorry was uninjured and a spokesman for Thames Valley police believed there was only one occupant in the BMW.

Police were continuing to investigate and called for anyone who witnessed the accident to contact them.

A statement from Watford read: "Davis was at the start of a season-long loan spell with the Hornets.

"The thoughts of all staff at Watford Football Club are with Jimmy's family at this time." FA chief executive Mark Palios told the Press Association: "We are deeply saddened by this tragic loss.

"It is terrible that a player so young, with such a promising career ahead of him, should lose his life in this way.

"Our sincere condolences go to Jimmy's family and all at Manchester United and Watford."

The football world yesterday paid tribute to the brief but glittering career of a Midland soccer star whose death in a car accident at the age of 21 marred the opening day of the new season.

Jimmy Davis (pictured), who was born in Bromsgrove, was killed when his grey BMW 3-series car was in collision with a DAF lorry on the M40 in Oxfordshire in the early hours of Saturday morning.

Davis, on loan from Manchester United to Watford, had been due to play at Vicarage Road against Coventry City in the Nationwide Division One fixture later that day.

The game was cancelled as a mark of respect.

There was a period of silence ahead of yesterday's Community Shield match between United and Arsenal and both teams wore black armbands.

A former pupil at Arrow Vale High School, in Redditch, Davis was a member of the England under-20 squad and tipped to become a future Manchester United star.

Manchester United manager Sir Alex Ferguson said: "You could not meet a nicer and more bubbly personality than Jimmy Davis."

Watford manager Ray Lewington and director football Terry Byrnes issued a statement: "We would like to express our deepest sympathies to Jimmy's family and girlfriend.

"In his short time at Watford football club, Jimmy had formed close relationships with everybody - players and staff - due to his happy-go-lucky personality.

"He will be missed greatly both on and off the pitch by everybody here and we would ask that everybody is allowed time and space to deal with this loss in their own way."

Graham Simpson, the chief executive of Watford FC, added: "It is a tragic blow and we feel very much for Jimmy's family.

"I saw him play three or four times, he was a player with immense potential and we were lucky to be able to have him here.

"Football pales into insignificance because today the life of a 21-year-old has been taken."

Mr Davis was pronounced dead at the scene of the accident and two lanes of the M40 were closed while investigators examined the scene. The driver of the lorry was uninjured and a spokesman for Thames Valley police believed there was only one occupant in the BMW.

Mr Davis went out on loan to Swindon last season, making 15 appearances for the Second Division club and scoring three goals.

He made his solitary appearance for the Red Devils in a Worthington Cup defeat to Arsenal on November 5, 2001.

Following his loan spell at Swindon, he returned to Old Trafford and was on the bench for the Champions League clash away to Deportivo La Coruna in March.

He signed professional forms with United in July 1999 and was capped by England at Under-20 level.