The comment was said after the women's 4x200 freestyle relay final. China's swimmer, 14-year old Ai Yanhan, lagged 1.61 seconds behind Canadian swimmer Taylor Ruck, who managed to win a bronze medal.
MacDonald thought he was not on-air and was heard saying, "The little 14-year-old from China dropped the ball, baby. Too excited, went out like stink, died like a pig. Thanks for that."
On Wednesday, netizens poured in comments and criticized MacDonald for his remarks. One Twitter user, Sarah Paradis, said, "Wow #ByronMacDonald. You represent the CBC and Canada and make us all sound like a bunch of racists."
Users from China also hit the sports commentator. One tweet read, "#Byron MacDonald# should be dismissed and @CBC Olympics stop use ctrl C + ctrl V, we need a real apology."
Other tweets stated that the commentator was "racist and insulting".
MacDonald went on air on Thursday and publicly apologized. He said, "I would like to take a moment to apologize for a comment that I made last night after the women's relay."
He added, "I was referring to a swimmer's performance, and not to them as a person. Needless to say, there was no disrespect intended and I'm very sorry."
CBC also apologized via Twitter for the incident, saying, "We apologize the comment on a swim performance made it to air. It was an unfortunate choice of words - we're sorry it happened."
CBC spokesman Chuck Thompson said, "We sincerely regret that these statements were made and that they were allowed to go to air. We moved quickly last night to apologize to our viewers on-air and to our followers on Social media."
In Sina Weibo, 2,300 users demanded that MacDonald is dismissed from CBC even after he made a public apology.
A slew of critticsms were given to sports journalists who were irresponsible for their on-air comments. A BBC reporter, Paul Hand, also said anti-gay remarks when Brazilian beach volleyball player Laura Franca gave a post match hug to her lesbian partner.
A BBC spokesperson apologized and said, "The comment was ill-judged and we apologise to any of our viewers who were offended,"