Burnley striker Andre Gray has been criticised after homophobic posts from his Twitter account were shared on social media.
One tweet from the 25-year-old Premier League player's account appeared to condone killing gay people.
The tweets date from 2012 - when the Premier League striker was playing for non-league Hinckley United.
The posts, which also contained offensive terms, were deleted on Saturday, soon after coming to light.
Campaign group Stonewall said such attitudes can become "a barrier to lesbian, gay, bi and trans people participating".
"While these tweets are of course historic, unfortunately homophobic attitudes and language continue to be an issue in sport, whether that's on the pitch, in the terraces or on social media," a spokesperson said.
"It's extremely important that we work together to kick these attitudes out of sport, and create supportive and inclusive environments that enable everyone to feel accepted without exception."
The tweets have led to thousands of social media users condemning the player.
One of Gray's tweets read: "Is it me or are there gays everywhere? #Burn #Die #Makesmesick".
The tweets were highlighted on the day Gray scored his first Premier League goal, helping Burnley to a 2-0 win over Liverpool at Turf Moor.
And it comes just a month after the player criticised two Burnley fans for racism during a pre-season friendly.
Both the club and the player are yet to respond.
