"True legend" in jazz circles is a frequently-used cliche. This time it's true. Rashied Ali is the man who pioneered an approach to drumming which threw out the traditional idea of the drummer as human metronome. His work with John Coltrane in the great saxophonist's final years is a high point of avant-garde creativity. It was Coltrane who coined the term "multi-directional" to describe Ali's loose, free style of rhythmic propulsion.

His current touring quintet with Greg Murphy (piano), Joris Teepe (bass), Josh Evans (trumpet) and Lawrence Clark (tenor saxophone) is playing a style which combines modern post-bop with Ali's trademark free jazz. During two hours at Pizza Express they performed only six tunes, averaging 20-30 minutes in length.

Every band member was given space for long improvisations on Jaco Pastorius's composition "Dania", which kicked off the night. Ali's revolutionary technique was evident from the start as he strayed in and out of timekeeping with an emphasis on snare drum usage. Second on the bill was the Monk classic "'Round Midnight" and the set ended with the ominous, fanfare-like melody of Coltrane's "Liberia". This was the first point at which the bass and piano dropped out, leaving Ali alone with Clark on saxophone. It was almost like two simultaneous solos, highly reminiscent of Coltrane's final studio album "Interstellar Space" which is a series of duets with Ali. The diners didn't know what had hit them; Saturday night in Knightsbridge is usually more genteel. It was a fitting tribute to 'Trane, with this concert coming days after the 40th anniversary of his death.

The second set featured two more standards and ended with "If only I had a Gig", the band's take on songs from The Wizard of Oz. There were further moments of sax-drums duelling, bassist Teepe produced one of the most melodic solos of the evening, playing on his own for several minutes, and Evans on trumpet also impressed with screamingly passionate lines.

Rashied Ali may be nearly 70, but his creative instincts continue to develop. His work with this young lineup constantly throws up new challenges and his solos burst with complexity. Hopefully this will carry on for some years to come.