Clapton's Crossroads: Jeff Beck, Steve Winwood soar, and B.B. King passes the torch to a new generation

1:12 p.m.: Alison Krauss’ Union Station is best in its five-piece acoustic bluegrass incarnation. When it expands to a seven-piece electric band, it sounds like a middle-of-the-road snooze, though Jerry Douglas’ lap slide guitar solo on “Far Side Bank of Jordan” is worth waking up for.

1:30 p.m.: Doyle Bramhall II, a pretty fair Texas guitar-slinger, performs his entire set from the comfort of a chair. Nothing wrong with that, but the back-porch vibe is surprisingly sleepy.

2:12 p.m.: Susan Tedeschi joins the set by her husband, guitarist Derek Trucks, and steals it. She storms through Junior Wells’ “Little by Little” and then teams with vocalist Mike Mattison for a roaring duet on Derek and the Dominoes’ “Anyday,” with Trucks adding a wicked slide solo

2:25 p.m.: Johnny Winter looks feeble as he slouches in from the wings, and slumps into a chair in front of the Trucks band. But once the black-hatted guitarist starts playing, the frailty melts. He tears into Bob Dylan’s “Highway 61,” and dispenses with the original’s ebb-and-flow momentum in favor of fierce linear drive. Once Winter’s 10-minute cameo is over, however, it becomes official: We have now heard enough slide guitar to last us several months.

2:40 p.m.: Robert Randolph sure can play that pedal-steel guitar. He turns his vamps into rave-ups that rely almost entirely on Randolph’s eye-popping instrumental dexterity rather than his far more circumscribed chops as a songwriter.

3:20 p.m.: Robert Cray’s so smooth, it’s possible to miss the rough edges in his protest song, “Twenty”: “They call this a war on terror/But I see a lot of civilians dying/Mothers, sons, fathers and daughters/Not to mention some friends of mine.”

3:50 p.m.: Post-war blues great Hubert Sumlin looks spry in his fedora, and he pays tribute to his old mentor Howlin’ Wolf with his percussive attack and brittle tone intact on “Killing Floor” and “Sitting On Top Of the World.”

4 p.m.: B.B. King enters and Cray, Sumlin and Jimmie Vaughan all defer to the 81-year-old master. King is in a frisky mood, wiggling his hips on a body that was built for comfort rather than speed. He carries on an animated conversation with his faithful guitar, Lucille, each vocal couplet answered by a string of equally expressive notes. The guitarist never tried to be the fastest gun in the blues corral, and he lubricates “Rock Me Baby” by refusing to force the tempo. For all the smiles King brings to the stage, his words suggest he’s passing the torch. He lavishes Clapton with praise (“I’ve never met a better man, a more generous man”) and he toasts the audience: “When they lay me off to rest, may the last voices I hear be yours.” He brings a renewed bite to “The Thrill is Gone,” slapping his fist against his palm, more outraged than resigned. And then he walks off,  amid hugs and tears.

4:52 p.m.: John Mayer’s “Waiting on the World to Change” may be the most spineless social-justice song ever written. It advocates a passive approach, whereas the song it most closely resembles --- Curtis Mayfield’s classic “People Get Ready” --- urges everyone to get involved, or risk being left behind. Mayer pulls his punches throughout a set heavy on spongy pop songs, until finally cutting loose on Ray Charles “I Don’t Need No Doctor.”

5:46 p.m.: Impish, white-haired guitar guru Albert Lee joins Vince Gill’s 12-piece band for an arched-eyebrow take on Johnny Burnette’s rockabilly scorcher “Tear It Up.”

6:01 p.m.: Alison Krauss joins Sheryl Crow to ask the musical question, “Are you strong enough to be my man?” Clapton then shares a microphone with Crow on Don Williams’ “Tulsa Time.”

6:12 p.m.: Willie Nelson joins Gill and strings together several of his signature tunes (“Funny How Time Slips Away,” “Crazy,” “Blue Eyes Crying in the Rain”) while playing the heck out of Trigger, his beat-up acoustic guitar. Though still justly celebrated for the honeyed tone of his conversational baritone voice, Nelson is such a gifted improviser he makes even his most-established songs sound fresh.

6:45 p.m.: Los Lobos is in top form, but the sound is less than stellar for a four-song set that concludes with the sax-and-guitar blow-out “Mas y Mas.”

7:45 p.m.: With his black-and-white vest and rooster haircut, Jeff Beck seems timeless. And his guitar prowess with a heavy duty jazz-fusion quartet is just as immune to aging. Beck’s sharp, piercing tone is sometimes softened by a slide, which he uses to tap out a beautiful melody on the strings. For the finale, he re-creates the vocal lines and orchestrations of the Beatles “A Day in the Life” on guitar with just his finger-tips and a whammy bar. As usual, there are no special effects or foot pedals, just Beck communing with his strings.

8:20 p.m.: Clapton has given some indifferent concerts in the last decade, but this is not one of them. The main reason is that he has a band that isn’t afraid to challenge him, particularly guitarist Derek Trucks and drummer Steve Jordan, who rises out of his seat just about every time he swats the ride cymbal. Trucks does most of the heavy lifting on the solos, bringing muscle to “Tell the Truth” and nuance to George Harrison’s “Isn’t it a Pity.” Clapton goes face to face with his young protégé on “Why Does Love Got to be So Sad,” and opens and closes “Queen of Spades” with passionate improvisations.

9:10 p.m.: Former Band guitarist Robbie Robertson joins Clapton for a rare concert appearance. The bespectacled Robertson honors Bo Diddley with a growling “Who Do You Love” and trades solos with Clapton and Trucks on “Further On Up the Road.”

9:20 p.m.: Steve Winwood joins the festivities, and leaves an indelible mark. He and Clapton team up for several songs from their old, prematurely dissolved band Blind Faith. The two share pleading vocals on a gorgeous “Presence of the Lord” and Winwood spruces up his soul-singer credentials on “Can’t Find My Way Home.” Though more celebrated as a singer and keyboardist, Winwood is also mighty fine guitarist  --- as he re-affirms on Traffic’s “Dear Mr. Fantasy.” Clapton returns to do the hackneyed “Cocaine,” but Robert Johnson’s “Crossroads” remains a rock-solid finale.

10:20 p.m.: Buddy Guy rounds out the night with a set long on showmanship and short on actual songs. So what else is new? Guy remains an astonishing guitarist; in terms of sound shaping, only Beck rivals his audacity. He brings out Clapton, and Cray, Winter, Mayer and others take turns running “Sweet Home Chicago” into the ground. The last hour feels anticlimactic, but the glow of knockout performances by Winwood, Beck and B.B. King more than compensates.

greg@gregkot.com