Wilco's influence over other musicians now appears to extend to bringing them back from the dead. The Chicago sextet, an inspiration to numerous younger bands thanks to their take on country and classic US rock, last night persuaded British singer-songwriter Bill Fay to make his first appearance on stage for more than 30 years.

Fay sold very few copies of two albums around the end of the Sixties, but Wilco leader Jeff Tweedy's wholehearted admiration brought him briefly out of the shadows here, to sing a short, touching version of his ballad Be Not So Fearful.

Before the surprise encore, the band had spent two hours demonstrating their skill at bridging the divide between musical genres. That divide was represented on stage by guitarist Nels Cline, their most recent addition, who looked and sounded nothing like his denim-clad bandmates with his sharp waistcoat and soloing.

Cline tacked a guitar freakout to almost every track. Sometimes, as on otherwise acoustic Via Chicago, the deliberate clash sounded forced. More often, as with the mesmerising, 15-minute Spiders (Kidsmoke), he added a thrilling extra dimension to a band already journeying well beyond the constraints of traditional songwriting.