On this new leg of Little Feat's 50th anniversary tour, the band needs an injury replacement because guitarist/singer Paul Barrere is sidelined with liver problems, it was announced late last week.

Like the Minnesota Twins in the playoffs without Byron Buxton and Michael Pineda, Little Feat suffered without their full lineup. At their first show with guitarist Larry Campbell sitting in, the band seemed tentative at times on Monday at the State Theatre in Minneapolis.

Actually, Campbell, who has toured with Bob Dylan and Levon Helm, seemed to be one of Little Feat's strong points, with his widely expressive guitar and robustly soulful voice. When he and fellow guitarist/mandolinist Fred Tackett got jamming together, they clearly were enjoying themselves – and the fans showed their appreciation.

However, too often during the 125-minute performance, Little Feat wasn't cooking like they can. Part of it could have been the injury replacement (Campbell has sat in with the band before but never filled in for an entire concert), part of it could have been the sound mix. The rhythm section wasn't loud enough for this listener.

Although the three-man horn section was consistently crisp, Little Feat came across like a jam band trying to find its mojo instead of funky, Southern-flavored Americana aces getting their groove on.

Indeed, the Feat have never been the same since founding singer/guitarist Lowell George died in 1979. But Barrere, keyboardist Billy Payne, bassist Ken Gradney, percussionist Sam Clayton and crew have carried on with new players who have come and gone.

Payne is the ringleader now, doing all the talking on Monday, handling most of the lead vocals and signaling for certain musicians to take solos. Early on, he acknowledged Barrere's absence and declared that he felt like an understudy on this night.

Despite that disclaimer, Payne, who also tours with the Doobie Brothers, often found Feat-tastic funkiness on piano and organ.

At the less-than-full theater, Little Feat delivered plenty of crowd favorites, including a mandolin-spiked "Willin'," a slow and swampy "Sailin' Shoes," the suitably sloppy "Fat Man in a Bath Tub," the slide-guitar fueled "Rocket in My Pocket," the New Orleans-seasoned "Dixie Chicken" and the boogieing "Oh Atlanta."

Highlights were the spirited "Rooster Rag," the rollicking "Let It Roll" and "All That You Dream," which evoked the underrated soul ensemble Delaney & Bonnie thanks to guest vocals by Teresa Williams, Campbell's wife and duo partner. (They were the scheduled opening act before Barrere had to bow out of this leg of the tour, so Campbell did double duty.)

At one point on Monday, Payne said that George called Little Feat "an experiment in terror." He paused and added, "It still is."

The Minnesota Twins might know something about terror these days.