THE Melbourne Storm yesterday dismissed any suggestion that it put lock Dallas Johnson at risk by playing him against South Sydney on Saturday night, three days after he was knocked out in a state-of-origin game.

A groggy Johnson was helped from the ground in the final minutes of Queensland's 18-10 loss after putting his head in the wrong position while attempting a tackle, which prompted Storm coach Craig Bellamy to declare the next day that Johnson would not play against the Rabbitohs if there was "a miniscule risk" to Johnson's health.

However, the 25-year-old passed a series of medical tests on Thursday night at the Storm camp at Gosford and after completing training on Friday without any subsequent problems, he was passed fit on game day, playing in the Storm's 15-10 win.

Storm high performance unit manager Mary Toomey said Johnson had fully recovered from the concussion — which she described as looking worse than was it was — and there was no additional benefit in resting him.

"There was no reason not to let him play. He was neurological and medically absolutely fine," Toomey said.

"If you do all those things (tests) and he passes them and he says he feels mentally ready to play, then there's no reason not to play him.".

Johnson's stumbling attempt to regain his feet on Wednesday revived images of a similar incident during last year's third origin game when he was knocked senseless in the first tackle.

Storm officials, including Bellamy, were last year furious about Queensland's decision to send Johnson back onto the field in the second half and subsequently rested him from the Storm's clash against South Sydney again, three days later.

Toomey said the situation last week was not as severe with the Maroons medical staff telling her that Johnson had "completely recovered within 30 minutes".

"He had a three-day recovery period this time. (Last year) he had 30 minutes and he was very definitely not completely recovered in terms of his concussion when he went back on in that game … I take a very strong position on managing the players safely and I believe that we did that.

"What Dallas had to do was convince us that he was fit to play and he was fit to play … the injury that he sustained on Wednesday night was not as bad (as what) people decided that it was based on the footage of him going down. It just wasn't that bad a concussion."

Johnson yesterday was adamant that he was fit to play."Obviously my health comes first, so I made sure the doctors cleared me and saw that I was fit and there was little risk," he said.

Toomey said there was no need to bring in a mandatory lay-off period for a player that received concussion — a concept previously discussed, and rejected, by the rugby league medical fraternity.

"It would cover all your bases and it would take some of the pressure out of making some of the decisions but … I think if you make good medical decisions it's not necessary to have that kind of rule," she said.

NRL chief operating officer Graham Annesley said it had been decided by the club chief medical officials that a "case by case" approach be taken on concussion victims.