LANCE THOMPSON will have to choose between a career in coaching or player management because of a new rule that prevents him from doing both.

Thompson's playing career ended in round six against Penrith due to knee problems, allowing the former Sharks forward to focus on managing his growing stable of players. The 30-year-old also recently took over as coach of Cronulla's NSW Cup side.

However, The Sun-Herald has learned that agents will no longer be accredited if they hold an "official position" in the game.

The development means Thompson, whose clients include Chase Stanley, Nathan Merritt, Kevin Kingston, Fraser Anderson and Misi Taulapapa, will have to relinquish one of his roles.

Told about this, Thompson said: "That's the first I've heard about it. I'll have to sit down, have a look and see what happens. I love doing both but I don't want to say too much until I learn exactly what's going on."

Cronulla chief executive Tony Zappia said it would be "disappointing" if Thompson had to quit coaching. "He took on that job before the rule was put in place, so I'd like to think that would be taken into consideration, at least for this season," Zappia said.

The Rugby League Accredited Player Agent Committee has rubber-stamped the new rule, which will forbid coaches, team managers, trainers, secretaries, directors or players from becoming agents.

"You can't be both," confirmed committee chairman Geoff Bellew.

"Once you get into district club or junior level, there's a potential for conflict. That can't be allowed because you could have an agent steering players towards a club because they have an affiliation with that club.

"I'm not casting aspersions on anybody, but you can't have a situation where that is a possibility.

"Players are being signed younger and younger and they have to be placed in a situation where they are getting the best possible advice."

Under the new rule, there would have been a potential conflict of interest for referee/manager John Hopoate. The former Manly winger helped broker a six-figure deal between the Sea Eagles and his son.

However, Hopoate snr recently gave up his management role. His business partner, Tyran Smith, is now the official agent for William Hopoate.