Los Lobos didn't play its No. 1 hit "La Bamba" until just before the encores at Merriweather Post Pavilion last night. As expected, the first chord threw the crowd into a dance frenzy, but the song was really just one stirring performance in a concert that held many.

For the entire show, the quintet played like the seasoned bar band it is. Although the group couldn't have been tighter rhythmically, it was David Hidalgo (on guitar and button accordion) and Cesar Rosas (on guitar and bajo sexto) who gave the music a distinct personality. With a strong assist from Steve Berlin, who doubled on tenor and baritone saxes, Rosas was largely responsible for the raunchy flavor and soulful insistence of blues tunes like "Why Do You Do" and "My Baby's Gone." Hidalgo, on the other hand, sang with the most feeling, especially when the band performed its best ballad, "Is This All There Is?" Together, they also made a couple of polkas, "Let's Say Goodnight ..." and "Come On Let's Go" so upbeat that they were impossible to resist.

The Smithereens, a band of New Jersey retro-rockers, opened the show by noisily resurrecting the '60s. While their approach to the music was hardly original, at least it was brash and unsentimental.