The former Liberal Democrat MP had to be taken away by St John's Ambulance paramedics on Saturday (June 2) after his bout against another wrestler, reports The Telegraph.
Opik has tried out various new career paths since he lost his seat in the 2010 general election, including stand-up comedy and appearing in a music video.
The politician had previously entered a wrestling ring wearing a suit back in April. Watch the 'fight' below:
He returned for a rematch with the wrestler in Welshpool, Powys on Saturday, wearing a T-shirt, tracksuit trousers and kneepads.
Opik was reportedly tossed around the ring from the early moments of the match, with one audience member describing the fight as "brutal".
He is said to have taken several blows to the face from Kade Callous, whom Opik had previously accused of cheating.
> Kerry Katona, Lembit Opik get cream pied on 'This Morning' - pictures
Attendee James Collins said: "He stood no chance, not at all. He looked so small next to his opponents, it was a tag team event but he took a battering, it was brutal to watch.
"He managed to get a couple of early blows away with the help of his team mate but there was no way the others were going to stand for that. It was obvious Callous was really angry about what happened before."
Fellow audience member Gene Jenkins said: "He obviously doesn't have a future in wrestling. He's tried so many things since politics, I think this is another failure.
"He looked in a real state when the paramedics carried him away from the ring."
Watch Lembit Opik in the video for 'Pop Wound' by The Good Suns below: