A MEDICAL expert insisted that former Blackburn Rovers star Martin Dahlin suffered a devastating back injury during training and any pre-existing condition did not cause his retirement.

Rovers are seeking £4million from their insurers in the High Court over the October 1997 incident, which eventually forced Swedish international Mr Dahlin to quit football.

But the insurers say Mr Dahlin already had a degenerative back condition and any claim should be dismissed.

Orthopaedic expert, John King, who treated Mr Dahlin said any degeneration in his back the striker was suffering at the time was "normal" for a man of his age.

Barrister, Jeremy Stuart-Smith QC, for the insurers, argued that the "prolapsed disc" Mr Dahlin suffered when he stretched for the ball in October 1997 could not have occurred "in absence" from a pre-existing condition.

"The consensus among the experts is that a prolapsed disc will not happen without a degree of degeneration of the disc," said Mr Stuart-Smith.

But Mr King said that, although Mr Dahlin's injury was "unusual" he had seen similar problems in 17 and 18-year-olds with no degeneration.

The expert admitted that 90per cent of prolapsed discs get better without requiring any surgery, but argued that even a fall of one or two per cent in Mr Dahlin's levels of fitness could be career-ending.

Although Mr Dahlin did play for Rovers after the incident, the club say he was never the same again, and, after moving to German outfit Hamburg, he was forced to retire in 1999.

"He never got back to the level of football he had been before the accident," said Mr King.

As well as the £4million compensation, Blackburn are also seeking interest on the sum, which was already £2million 18 months ago.

The case is continuing but it was due to finish later this week.