The Grateful Dead's virtuoso bass player Phil Lesh opened the "Phil & Friends/Bob Dylan" concert Monday night at the Baltimore Arena with a long-evolving jam that segued into the Dead mainstay "Morning Dew." But if Lesh's sometimes labored vocals left "Dew" on the ground, his makeshift band nonetheless moved forcefully into "The Wheel" with thundering harmonies that masked occasional discord from too little rehearsal together.

Derek Trucks, the kid phenom from the Allman Brothers Band, took over lead guitar duties less than two weeks ago when Steve Kimock unexpectedly bolted. With Warren Haynes, another Allman expatriate, handling the other lead guitar, Rob Bracco of the Dead-cover band Zen Tricksters on keyboards and John Molo on drums, various Allman and Dead styles commingled and collided throughout the many jazzy jams.

Momentum soared with a tight "Playin' in the Band." The fast-paced version of the Youngbloods' "Get Together" suited Lesh's voice better than the sweetly played "Cold Rain and Snow" that ended the promising 90-minute set.

An unusually gregarious Bob Dylan set the tone for the next two hours with a highly articulated, staccato "Mr. Tambourine Man." A melodic "Visions of Johanna" and a robust "Tangled Up in Blue" followed. The black-jacketed troubadour turned from acoustic to electric for a nasty "Big River" and a high-powered "Tombstone Blues." To the Deadhead-dominant audience's approval, Lesh joined Dylan for two encores--a raggedly compelling "Friend of the Devil" and a raucous, lights-up "Not Fade Away."