He looked like a professor at a Christian college, wearing a brown blazer, tie, vest and neatly trimmed beard. He sang like an undertaker, in a flat, deep, sorrowful voice.

Nevertheless, Matt Berninger came off like a true -- albeit unlikely -- rock star Thursday at First Avenue, the first of two sold-out nights with his critically acclaimed (and now commercially bubbling) rock band the National.

Sounding like a depressed and disenchanted U2 or a rhythmic and melodic Leonard Cohen, the Ohioan-via-New-York quintet played a commanding 100-minute set in which Berninger effortlessly commandeered the spotlight. His poetic lyrics about urban isolation and modern disconnection had the mostly collegiate or post-collegiate crowd mouthing along to both old and new songs. His writhing movements and microphone-stand-grabbing antics were dramatic but not flashy. And he masterfully saved his most frantic, screaming vocal bursts until they really meant something, be it the beginning of "Abel" or the climactic end of "Available" and "Terrible Love" -- the latter of which he finished howling out from deep within the crowd.

Behind the frontman, the rest of the National -- two sets of brothers -- overtly stepped up their game. A configuration they also brought to First Ave last year, the band expanded with four extra members: three horn players and a violinist/keyboardist. The auxiliary guys weren't just for show, either. They figured prominently throughout the set, bringing elegance or sheer chaos, depending on what was required.

The National is a band that likes to mess with and sometimes outright tear up its arrangements. It reportedly re-arranged one new song about 200 times during recording of its new record, "High Violet." Several of the songs in Thursday's set (new and old) were noticeably changed. For the worse, the horn parts spiked into "Slow Show" felt clumsy and distracting, and the normally triumphant "Apartment Story" lagged a bit with staggered rhythms. For the better, "Squalor Victoria" was turned into a near-frantic marching song, and the new gem "I'm Afraid of Everyone" actually came off frightening.

"High Violet" (the band's fifth disc) is a pretty mopey record, to the point of occasionally being drab. However, many of its songs carried a heavier, punchier sound on stage, including the riveting "Bloodbuzz Ohio;" or else they came off with more of a humming elegance, including the opener "Runaway."

"What makes you think I enjoy being led to the flood?" Berninger sang in "Runaway," setting the bleak and oblique tone of his lyrics. "We've got another thing coming undone."

The frontman showed off his lighter, wry-humored side after telling the crowd how great it is to be back at First Ave. When a bandmate asked how many times they've been there, the singer replied, "For all I know, we've never been here."

One thing's for sure: It could be quite a while before the National is back at the club, but its graduation to bigger venues is well deserved.

See the National's set list at startribune.com/artcetera. Chris Riemenschneider • 612-673-4658