Former Republic of Ireland midfielder Ray Houghton has called the online abuse of Cyrus Christie shameful and said representing the country has never been about a player's race.
Middlesbrough defender Christie was targeted by some posters on social media following Ireland's 5-1 World Cup play-off defeat to Denmark, in which he scored an own-goal, and last night expressed his sadness that "racism is still part of the game we all enjoy and love."
Christie called on all football fans "to stand up against these individuals who do not belong in football or any other sport."
The FAI have reported the abuse to Gardai.
Like the England-born Christie, Glasgow native Houghton qualified to play for Ireland through his family heritage.
"It's dreadful," Houghton told RTÉ Sport. "Shameful, the behaviour of people on social media.
"Cyrus is an extremely good footballer.
"One of the great things about playing for Ireland is that it was never about the colour of your skin, it was always about pride in the shirt and giving 100%.
"It was about your attitude and committment and certainly Cyrus has shown that in all the matches he has played for the country."
Houghton called on social media sites to get tougher on people spouting abuse online.
He said: "You do get keyboard wizards who come out and write things about certain individuals and think they can get away with it but I hope the authorities are on to them and they get what they deserve.
"With social media, we've opened up a can of worms. Anyone can go on there and write what they want.
"The people who are running these websites have got to be more diligent about what's going on and make sure the authorities are given the ability to catch them and punish them for what they're doing."