Hulk Hogan is in constant agony, according to wrestling legend Ric Flair.

The grappler-and-reality TV star is suffering from a serious back injury which could mean he never competes in the ring again.

Flair - who is a member of the Total Nonstop Action (TNA) Wrestling roster with Hogan - told BANG Showbiz: "His heart is in the ring but he has health issues and at this point in time they are overwhelming. His back has been really bad. He's got an artificial knee, an artificial hip, which don't bother him at all. But his back is causing everything to hurt."

However, Flair - who has been in several matches with Hogan on TNA's flagship show 'iMPACT' since the two superstars joined the company in January - hopes his long-time rival will be able to carry on wrestling.

The 61-year-old former multi-time world champion added: "Hopefully, when he gets his back fixed he'll be fine. We might still see him in the ring if his health issues get resolved."

Although Flair has had on-screen rivalries with 56-year-old Hogan - who previously starred in reality TV show 'Hogan Knows Best' with his family, including his pop star daughter Brooke Hogan - for decades, he insists he has enormous respect for him.

He said: "I respect him immensely but on some things we agree to disagree. It's the business."