Then I saw his face. Oy vey!

Neil Diamond with a beard?

Leave the grandpa beard to Mandy Patinkin, John Mellencamp and Barry Gibb.

Then I heard his voice. Now I’m a believer. Not a trace of doubt in my mind.

“I couldn’t leave her even if I tried,” Diamond growled on that song he wrote for the Monkees. “Cause I’m a believer.”

It was easy to be a believer in Neil Diamond Sunday night at sold-out Xcel Energy Center whether you looked like you were attending an AARP Convention (most of the 13,000 fans) or came still wearing your hipster Coachella festival admission bracelet (the dude next to me) or sporting your Red Sox colors (the twenty-something dude behind me who sang “Sweet Caroline” like it was the eighth inning stretch at Boston’s Fenway Park).

From the opening song (“I’m a Believer”) to the closing number (“Heartlight”), Diamond has never been in better voice in concert in the Twin Cities. He belted his “todays” in “America,” sustained his note near the end of “Play Me,” and bellowed a satisfying “yeah” as a postscript to “Better Days,” a new song. But his series of declarative “yeahs” in the home stretch of “Holly Holy,” the night’s highlight, were heavenly, buoyed by the backup duo known as the Waters Sisters who gloriously gospelized this song.

Not only was Diamond in great voice on Sunday, he seemed to be in good spirits. OK, it was only one concert in the Twin Cities this time instead of the usual two (or three, back in the day). But he seemed re-energized with a slightly revamped band, three new songs and his silvery stubble and blackish mustache (which made him look sinister, especially with those dark eyebrows).

At 74, Diamond hardly moves like Jagger even if his legs are as skinny as Mick’s. But he worked the stage, bouncing to the beat, slow-dancing with himself on ballads and making those grand hand and arm gestures. He’s got more histrionic ways to end a song — the hands in the air, the finger pointing, the arms spread wide, the blowing of kisses — than Jagger has prances and struts down a runway.

Diamond always has had a sense of drama, in performance and in musical arrangement. “I Am … I Said,” his overwrought autobiography that takes him from wallowing in loneliness to celebrating his triumphant life, was a dramatic high point for fans in St. Paul, but “Brooklyn Roads,” a vividly detailed account of his childhood, seemed to resonate more emotionally with the singer.

Ultimately, though, Diamond’s concerts are about those infectious earworms that he has created. Even Minnesota fans who can’t clap on the beat clapped along Sunday, including to the Latin-tinged “Beautiful Noise,” the acoustic guitar-driven “Cherry Cherry” and perpetually peppy “Forever in Blue Jeans.”

“Cracklin’ Rosie” and “Sweet Caroline,” the one-two punch that started the encore, turned into giant singalongs because they’re karaoke classics, earworms that can’t be extinguished.

Diamond’s three new numbers from last year’s “Melody Road” album demonstrated once again his gift for melody and fondness for sentimental lyrics. Corny and schmaltzy describe “Nothing But a Heartache,” “In Better Days” and “The Art of Love,” whose lyrics Hallmark would have sent back for a rewrite. They are not worthy of the rock Hall of Famer who gave us “Kentucky Woman,” “Song Sung Blue” and “You Don’t Bring Me Flowers,” none of which were performed Sunday.

Maybe it’s time to shave those new songs — and that beard.