Carolina Panthers tight end Greg Olsen missed his third straight practice Thursday, but coach Ron Rivera was adamant there's no reason to worry about Olsen's long-term status.

An MRI on Olsen, who suffered back spasms after Sunday's practice, confirmed the Pro Bowler isn't dealing with any structural damage. It's unlikely he'll play in Saturday's preseason game at Tennessee, and because he's a 10th-year veteran with little to prove, it wouldn't be surprising if the Panthers rest him until the season opener in Denver.

"It's nothing to be concerned about," Rivera said.

"Greg's a veteran guy. He's seeing the doctors. He's just going to continue and he'll be back on the football field."

Olsen has missed just four preseason games in his career. The last time he sat out a regular-season game was early in his rookie year. His 142 consecutive games played since 2007 is second-longest among active tight ends behind Dallas' Jason Witten (203).

Olsen's 64 straight starts in Carolina is the fifth-longest streak in team history.