Gay footballers coming out would help boost the cause of equality, Commons Speaker John Bercow has said.
Mr Bercow said it would "do wonders for the cause" if players felt able to be open about their sexuality, adding that it was "wholly implausible" that there were not gay stars in the top tier of the sport.
At an event hosted by the Speaker, former Welsh rugby captain Gareth Thomas - who came out in 2009 and has campaigned to tackle homophobia in sport - said he wanted to create a culture where players or coaching staff "wouldn't face criticism or abuse for being who they are".
Thomas, who also captained the British Lions, was in Westminster to back a change in the law which would make homophobic abuse at football grounds illegal in the same way that racism is.
Mr Bercow, who was hosting a reception in Westminster for those campaigning for a change in the law, said: "I do find it really odd in football that people just don't come out as gay.
"On the law of averages I just find it literally inconceivable, wholly implausible, that in Premier League clubs and across the divisions there aren't gay footballers.
"I just find this really odd."
Arsenal fan Mr Bercow said: "I have to say I do think it would do wonders for the cause of LGBT equality if people felt able, felt they had the space and the freedom and the protection and the support ... to come out and say, 'This is who I am'."
He praised the efforts made by his club, and added: "If we are at least to create a climate in which people feel they can say, 'This is me, I am first and foremost preoccupied with playing football but by the way I'm gay' or, 'By the way I'm bisexual' that would be such a healthy place to reach."
Asked about Mr Bercow's comments, Thomas told the Press Association "it would challenge opinions, I'm not sure it would change opinions" if a player came out.
He said he wanted to create an environment where players or staff could come out without fear.
"I think that's the overwhelmingly important message from today, is to create the environment," he said.
"I don't think any sports really are in the clear, all sport needs to try and catch up.
"Football is the world-dominating game, it's the most publicised game, it's the most played game, it's the most watched."
Because of that status, football "could be a leader in this rather than a follower".
Thomas said when he attends football or rugby matches he still hears homophobic comments, although not aimed at him.
"I get insulted at people shouting at other people, homophobic comments not directed at me.
"But it sometimes happens when people see me, they realise that would be offensive to me so they don't say it - it's like, well why would you say it in the first place?
"That's the whole thing of creating that environment where, regardless of who is around you, regardless of who is saying that, it's an offence to do it so people would think twice about doing it, rather than think twice because there is somebody who is openly gay with them."
Damian Collins, chairman of the Digital, Culture, Media and Sport Committee, is leading efforts to change the law by amending the 1991 Football Offences Act to put homophobic abuse on a par with racism.
The move would outlaw "chanting or gesturing in relation to a person's sexual orientation or gender reassignment".
He said there was a concern about "whether there remains an atmosphere or a culture around homophobia in football which makes it difficult for people to be open about themselves and their lives and people that they love".
"It could be one of the reasons why we have no openly gay footballers playing in the senior levels of professional football," he said.
Mr Collins urged the Government to back the Football (Offences) (Amendment) Bill to make sure it progresses through Parliament.
He said he had been in touch with sports minister Tracey Crouch about his plan.
Paul Elliott, chairman of the FA's inclusion advisory board, wrote to Mr Collins to offer his support.
"The FA has long called for the criminalisation of homophobic chanting at football matches, and we are therefore delighted that you agree that this would be a valuable action for government to take," he said.