Sunday night at the Manship Theatre, Steve Martin, actor, comedian, playwright and best-selling author, displayed another of his many talents. Although he told numerous jokes, smoothly weaving the comedy he’s famous for into a nearly two-hour show, Martin and the Steep Canyon Rangers mostly played a genuine bluegrass concert.

After decades of success in movies, the 66-year-old Martin, a banjo lover since his teens, recently brought his musical talent to the forefront.

With mock pretentiousness, Martin informed the crowd that his 2009 debut, “The Crow: New Songs For The Five-String Banjo,” won a Grammy award for best bluegrass album. And, by the way, the International Bluegrass Music Association recently nominated his 2011 album with the Steep Canyon Rangers, “Rare Bird Alert,” for album of the year.

Sunday’s long-sold-out show in Baton Rouge confirmed that Martin and the Rangers’ deserve the attention. The concert featured a strong set of songs and instrumentals composed almost exclusively by Martin.

Even so, it all began with a joke. After making his entrance with the five-man, North Carolina-based Steep Canyon Rangers, Martin surveyed the full house and said, “Oh, boy. I wish I’d practiced.”

It was obvious, though, that not only had he practiced, he’d practiced with the band. That’s something relatively new for the longtime solo banjo man. And with the Rangers playing, as the old Lovin’ Spoonful song says, clean as country water, Martin and the band’s ensemble blend rolled flawlessly forward.

Opening the show with a swift instrumental, “Pitkin County Turnaround,” Martin proved he’s not kidding about this bluegrass thing. In traditional bluegrass style, too, fiddler Nicky Sanders, guitarist Woody Platt and mandolin player Mike Guggino all took solos. Martin played a banjo break, too, though he usually took the role of team player.

Rangers principal vocalist Platt sang lead for the faux nostalgia of “Daddy Played The Banjo” and conflicted love song, “Go Away, Stop, Turn Around, Come Back.”

“I like to write songs about love,” Martin said while introducing the latter song. “Because love is so infinitely complex that you can almost say anything in a love song and it will be true for someone.”

As the four vocalizing members of the Steep Canyon Rangers sang “I’m walking away” into a single mic, comedy and old-time bluegrass combined for “Jubilation Day.” In one of the night’s few songs starring Martin’s lead vocals, no tears were shed as he played the part of a man thrilled to be rid of his tortuous ex.

“Even your mom said you were nuts!” Martin sings. “You wear a red cape and pitchfork.”

Turning the other cheek, Martin dedicated the non-sarcastic “Best Love” to his wife. Sung by Rangers fiddler Nicky Sanders (and Paul McCartney on the CD), this lovely selection showed the warm, melodic side of Martin’s songwriting.

The gospel-styled “Atheists Don’t Have No Songs,” sung a cappella by the mic-sharing Martin and harmonizing Rangers, was another clever blend of comedy and song.

“No one ever wrote a tune for godless existentialism,” the Rangers proclaimed. “Atheists don’t have no soul! Atheists just sing the blues.”

The show’s other highlights included “Wally On The Run,” a cute, bursting-with-joy duet performed by the banjo-picking Martin and the Rangers’ virtuoso fiddler. A theatrical piece with spoken dialogue and barking and whining effects, “Wally” depicts a reluctant dog owner and the canine who insists upon playing ball.

And for an encore, the group ended their frequently funny, musically superb show with a tour de force take on that fiddle-showcasing bluegrass barnburner, “Orange Blossom Special.”