Marcus Urban played for German second division team Rot-Weiß Erfurt in the 1990s, but came out as gay man at a time when it was almost unheard of for a footballer.
Despite it being more accepted now to be a gay man, there are still no openly gay players in all the teams at Euro 2012.
Urban has teamed up with campaign group AllOut.org to live tweet during England's crucial Group D clash against the Ukraine, starting from 7.30pm tonight (June 19).
They want to raise awareness of the fact that the parliament in Ukraine is currently considering a "gay gag rule", which would make it illegal to say the word "gay" in public.
AllOut.org has launched an international campaign to urge president Viktor Yanukovych to speak up against the growing anti-gay sentiment across the Ukraine.
"The situation for lesbian and gay people here in Ukraine is urgent, and we need supporters like Marcus and All Out members all around the world to speak up with us", said Zoryan Kis, executive director of Fulcrum, a Ukrainian LGBT organisation.
The British government has boycotted the group stage of Euro 2012 in protest at the situation, as well as the jailing of Ukrainian opposition leader Yulia Tymoshenko.
Tymoshenko has been charged with the killing of the businessman and MP Yevhen Shcherban 16 years ago, but her party claim that the charges are part of Yanukovych's campaign to eliminate his political opponents.
"Leaders are telling Ukraine that they can not reap the benefits of the European community while rejecting its commitment to human rights," said Andre Banks, executive director of AllOut.org.
"Euro 2012 has become the focal point for everyone from heads of state to pro-footballers ready to give Ukraine a red card for the country's ever expanding pattern of human rights abuses."
But also the protest is aimed at showing how difficult it still is for footballers to come out as gay.
Marcus Urban said that he quit football 20 years ago due to the "pressure to conform" in the professional game, and he feels that those pressures still exist for players today.
"Even now, just a few days ago, an Italian forward playing at Euro 2012 said that he hopes there are no gay players in his team," he said.
"He is a typical example of how little football has advanced on this issue in the last two decades. As a matter of fact, there are no openly gay players at the Euro 2012 at all."