John Martyn, Roundhouse, London <!-- none onestar twostar threestar fourstar fivestar -->

John Martyn's singing style and innovations with echo-effects and fuzz-box guitar pedals in the early 1970s were influenced by the free-jazz saxophonist Pharoah Sanders. On the albums Bless the Weather, Solid Air and Inside Out, he set out to replicate Sanders's incredibly long sustains with his voice and guitar playing.

The textured, multi-layered soundscapes he created as a result found their most complete expression in 1973's Solid Air. Martyn's performance of that album at the Barbican last September as part of the Don't Look Back series earned him glowing praise, and at times tonight you can see why.

This ravaged man, wheel-chair-bound after having his lower right leg amputated, slurs incoherently between songs and presents a figure of often heartbreaking pathos, but his singing and guitar playing are still capable of great emotional heft and beauty. There's a lot of love in the room, and rightly so.

However, if the saxophone moved Martyn to make some of the most diverse folk rock of the 1970s, its presence this evening has a more malign effect. It's hard to totally flatten such timeless classics as "Solid Air" and "May You Never", but Martyn's saxophonist, Martin Winning, very nearly pulls it off. There wasn't a space in Solid Air's expansively structured sound that he wasn't determined to fill.

It was instructive that the high point of the night was when someone persuaded Winning to leave the stage for one song, "Over the Hill". Martyn's acoustic playing dovetailed with Alan Thompson's mandolin in a delightful recital that evoked some of Solid Air's wide-open latitude. But then Winning was back, hankering to make up for the precious five minutes of the whole 90 that he wasn't flatulently plugging those all-important gaps in Martyn's fluid, improvised arrangements.

It's hard to convey just how debilitating these crass, exasperating sax solos were. The two covers at the end, of Utah Phillips's "Rock Salt and Nails" and Joe Scott's "Never Let Me Go", wouldn't have sounded out of place at a Russian oligarch's wedding. Hall and Oates would've balked at the sheer pomposity and duration of Winning's climactic coup de grâce as Martyn was carried from the stage like a mad medieval king.

This great but damaged British maverick is crying out for younger, more dynamic musicians to save him in the way that LA band the Wondermints revitalised Brian Wilson. Martyn's 1996 album, And, helmed by the Chicagoan hip-producer Stefon Taylor at a time when the 58-year-old was being fêted by the likes of Portishead as a godfather of trip-hop, suggests that such a collaboration could be fruitful. Or maybe he needs to fall in love with the Pharoah Sanders school of saxophone playing all over again.