WILCO AND FLEET FOXES, Red Butte Garden, Monday

Watching Wilco perform live is like visiting the great Catalan city on the eastern coast of Spain: eclectic, modern, creative. Especially creative.

In fact, the creative energy seems to crash like tidal waves from the stage, just as it overwhelms a visitor to Barcelona. It is a mysterious, yet unmistakable, rush of energy.

From the opening sounds of "Remember the Mountain Bed" to the closing rim shots of "Kingpin," Wilco proved repeatedly why it is the greatest American rock band of this century and one of the greatest of any era. It fills an amplifier like Picasso covered a canvas.

Too much? Bombastic? Over the top? Picasso — seriously?

Seriously. The band is that good, and any doubts otherwise were laid to rest Monday night at Red Butte Garden.

There has never been any question about Jeff Tweedy's talent as a musician and a lyricist, since the Uncle Tupelo days. He is the Joan Brossa of modern American music.

However, he is complemented by some of the finest musicians playing today, most notably, Nels Cline. On many songs — especially "Via Chicago" and "Poor Places" on Monday night — Cline shaped feedback into masterpiece, the same way Dali shaped crooked geometry into poetry.

On drums, Glenn Kotche is the Antoni Gaudi of the band, with his ability to elevate the role of "Heavy Metal Drummer" into something akin to a deity. The normally straight lines of a rock drummer are warped by Kotche, who often seems to have sprouted a third, or even a fourth, arm during his playing.

What Wilco creates on stage is as much modern art as it is music. Because of that, it is challenging, but the audience is growing, and the fans, a passionate bunch, appreciate the strokes of genius.

On Monday night, practically every song in the band's set — which included 21 songs, two encores and lasted well over two hours — could be called a masterpiece. But the best of a remarkably strong set were "Via Chicago," the always classic "Jesus, Etc.," "Spiders (Kidsmoke)" and the all-out jam "I'm the Man Who Loves You."

As an added bonus, Tweedy was also very funny, poking fun at the freeloaders sitting on the hill above the amphitheater ("Somebody will be up there with a hat, collecting money"), the name of the venue, and rock 'n' roll pretensions such as the call-and-response or encores.

The Seattle-based Fleet Foxes, which specializes in delicate harmonies and soaring melodies, played a short but extremely strong set to open. The talent of Fleet Foxes, in fact, only served to emphasize how well Wilco really played.

Wilco's greatness, in the wider context, will remain a subject of debate. But Monday night's show was easily one of the best ever played in Red Butte, if not anywhere.

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