It would not be too much of an exaggeration to suggest that the saxophonist Mike Osborne was the Syd Barrett of the jazz world. Both musicians came from provincial middle-class backgrounds, enjoyed a brief period in the London limelight as ferociously productive innovators and then, suffering from the excesses of the musical life in conjunction with mental problems, retreated to their homes in the provinces, to survive for decades in obscurity until overtaken by an inevitable lonely end.

Mike Osborne was the most brilliant alto saxophonist of his generation, and was not only the star soloist in Mike Westbrook’s innovative big bands of the 1960s, but a vital member of bands led by the South African musicians Chris McGregor and Harry Miller, and of the saxophone trio SOS. His tart, acidic tone owed a lot to his American idol Jackie McLean, and the phrasing of his early work drew on the distinctive contours of Ornette Coleman’s playing. But Osborne’s great gift, even as a young soloist in his twenties, was to communicate deep emotions, entirely without reserve. This made his contributions to Westbrook’s 1969 anti-war jazz symphony Marching Song particularly effective, and few who have heard Osborne’s tortured playing on the movements Ballad and Tarnished will have come away unmoved by the soul-baring of his sound.

Michael Evans Osborne was born in Hereford, where his father worked for the local authority and his mother owned a hair salon. He learnt the violin as a child, but after an education at Wycliffe College in Gloucestershire, at the age of 18 he moved to

London to study the clarinet and piano at the Guildhall School of Music and Drama.

Not long after his arrival in London, he was drawn into the orbit of the pianist, composer and bandleader Mike Westbrook, who had organised his first bands at Plymouth College of Art, but who moved permanently to London in 1963 and founded the most dazzlingly original big band of the period. In its ranks, alongside the clean-shaven, crew-cut, besuited Osborne, sat the saxophonist John Surman, trombonist Malcolm Griffiths and bassist Harry Miller, all of whom were to make their individual marks on the jazz of that decade.

Westbrook’s albums Release, Celebration and Marching Song have been regarded widely as heralding a new era in British jazz, in which it was shedding American models and finding a true and original voice of its own. Osborne’s distinctive playing was a key element in that process, and he became widely in demand as a soloist, working with the big bands of John Warren and Mike Gibbs, as well as with Chris McGregor’s South African big band, the Brotherhood of Breath.

Stylistically, Osborne was able to blend his distinctive sound into various contexts and it was not unusual to open the Melody Maker in the late 1960s and find that he was working one night with Humphrey Lyttelton’s mainstream swing band, and the next with John Surman’s experimental quartet or octet.

By now, Osborne’s hair and beard had grown, and as he shed sartorial formality, so, too, did he open up the boundaries of his playing. His early 1970s albums Outback, a quintet, and the trios Border Crossing and All Night Long, showed a musician who had created an immediately recognisable solo voice, playing alongside Miller and the South African drummer Louis Moholo, with sustained passionate intensity.

He also became a founder member with Surman and the tenor saxophonist Alan Skidmore, of the trio SOS, which presaged the fashion for unaccompanied saxophone groups of the 1980s and 1990s. As well as recording an acclaimed album (which was reissued last year) the trio played a season at the Paris Opera in the ballet Sablier Prison. In it, the group appeared live on stage, playing music written to accompany Carolyn Carlson’s choreography, before audiences who — in a break with tradition — were allowed to enter the auditorium in jeans and T-shirts.

By the mid-1970s, with a series of wins as Best Altoist in the annual Melody Maker poll behind him, Osborne looked set to consolidate his position as the most talented exponent of his instrument that Britain had ever produced. The albums Marcel’s Muse and Live at the Plough, from 1977 and 1979 respectively, appeared to confirm this. But by the late 1970s he had already had paranoid schizophrenia diagnosed, and as his behaviour became more erratic, he gradually withdrew from the London jazz scene. A move to Norfolk, with his wife at that time, Louise, did not alleviate his condition, and by 1980 he had practically given up playing. He finally withdrew from music completely in 1982, and settled back in his home town of Hereford, where he lived in care.

He did play once or twice with friends in the early 1990s, but the possibility of a return to professional performance was ruled out, and he remained away from the public eye, save for the reissue on CD over the past decade of several of his seminal albums. These offered a poignant reminder of the formidable talent that his lengthy illness had removed from British jazz.

Mike Osborne, jazz saxophonist, was born on September 28, 1941. He died of lung cancer on September 19, 2007, aged 65