Dave Matthews Band’s Saturday concert at Mohegan Sun Arena was a study in Effortless Cool.

From the start, when Matthews ambled onstage with an endearing modesty, to the musical-fireworks finale three hours later, Matthews’ performance and the group’s chemistry were golden.

Each jam was potent, with musicians blending perfectly and then letting each other step forward in the spotlight. While everyone (super drummer Carter Beauford, bassist Stefan Lessard, guitarist Tim Reynolds, saxophonist Jeff Coffin and trumpet player Rashawn Ross) impressed, the give-and-take between Matthews and violinist Boyd Tinsley bristled with the most electricity - so much fun to watch and hear.

Matthews - as always, confident without carrying any rock-star artifice - was in fine from. His distinctive vocals curled their way around each lyric. His guitar-playing and even his piano-playing, on the lovely “Out of My Hands,” spoke expressively.

This was DMB’s first concert ever at Mohegan Sun, and, boy, was the audience jazzed. Their enthusiasm never waned, and it especially fired up on more familiar songs like “Don’t Drink the Water,” during which they happily sang along and raised their arms in the air.

DMB isn’t a band that feels compelled to trot out all its greatest hits - no “Crash into Me,” no “What Would You Say” - but it packed a rich set list regardless. It culled some of the strongest tunes from its new album, “Away from the World,” and it wrapped the night up with a knock-out: DMB’s dramatic take on “All Along the Watchtower.”

While Matthews kept his between-song words to a minimum, he did make a reference to the casino locale, joking about slot machines. Back in “the olden days,” he says, he liked the slots when they were one-armed bandits - and he created cartoony sounds of lever-pulling and wheel-spinning. Now, he says, it’s just pushing a button - he imitated a soft pop - and then he sputtered, “Money gone. Money gone. Money gone.”

A note on the concert’s light show: the lights started off beautifully accenting each song, as if they were merely another instrument. Over the course of the night, though, they worked themselves into a frenzy, flashing and pulsating and ultimately distracting from the music.

Saturday’s opening act was reggae legend and Rock and Roll Hall of Fame member Jimmy Cliff, who, at age 64, still possesses the vocal chops and the sprite-like energy of a youngster. He performed some of his best-known numbers, including his cover of “I Can See Clearly Now,” and he turned his own protest song “Vietnam” into “Afghanistan.”