Mr Simmons (r) has been a regular Egghead since 2008
The BBC has defended Egghead star Barry Simmons' right to compete in the final of Radio 4's Brain of Britain quiz.
The Sunday Telegraph , externalhas reported five complaints were made to the corporation about Mr Simmons' successful appearance in the competition's semi-final.
He will compete in the final next week.
A BBC statement said: "There is no rule banning Eggheads from appearing on Brain of Britain - the only rule is that former champions are not allowed to return."
It added: "Brain of Britain is a very unpredictable quiz and it is quite possible a well-known quizzer like Barry could be beaten."
Professional quizzer Mr Simmons has also appeared on Who Wants to Be a Millionaire?, where he won £64,000 and was a semi-finalist on Mastermind.
In 2009, he also reached the final of Brain of Britain, but was defeated by Geoff Thomas.
Eggheads is a quiz show on BBC Two, co-hosted by Jeremy Vine and Dermot Murnaghan, in which a team of five challengers pits their wits against a a team of five 'Eggheads' - all highly regarded quiz and game show champions.
Brain of Britain is a nationwide general knowledge contest in which 48 listeners from all parts of the United Kingdom compete for the title.
The 2007 champion, Kevin Ashman, is also a regular on Eggheads.
The row has been picked up on Twitter where Marilyn Stowe has written,, external "What a nasty piece about one of the greatest Geeks in the country! If he wins Brain of Britain that's because he is!"
Mistress_Fiona said, external: "BBC in row over 'professional quizzer' on Brain of Britain - he is paid by BBC to appear on Eggheads!"
But addressing the row, external on Twitter, Mr Simmons wrote: "My appearances on Brain of Britain appear to have caused a minor stir. Let me remind everyone the program is called Brain of Britain!"
