Friendships run deep in jazz, where mutual musical respect counts for more than money and generally outlasts it. Guitar icon Pat Metheny was only 19 when vibraphonist Gary Burton gave him his first proper job. Metheny was grateful and learned a lot. He stayed for four years, and last night, three decades later, was happy to cede top billing to his old boss.

"Being on this tour is an absolute thrill for me on every level," declared the haystack-haired star after five scintillating numbers by The Gary Burton Quartet Revisited, to use the event's official title. "In fact the two most important musicians to me, Gary Burton and Steve Swallow, are right here on this stage."

Time had treated some more kindly than others. In the stage half-light, bass-guitarist Swallow resembled Albert Steptoe but there was nothing rusty about his technique. Like Burton and Metheny he played brilliantly, with far more expression than in the old days. Dedicated musicians keep improving and the baby of the group, Mexican drummer Antonio Sanchez, had to work hard to keep up with these veterans on a clammy evening.

Burton's four-mallet technique was easily up to pieces by Chick Corea, Keith Jarrett and bassman Swallow. But the duet-sections with Metheny (for a ballad, Angel Eyes, and bossanova, O Grande Amor) were the outstanding moments. The worst were Metheny's guitar-synth "trumpet" solos and his 42-string multiplenecked novelty guitar number.