Cliftonville beat Glentoran 1-0 in the Irish Premiership on Friday night. The winner came via Joe Gormley six minutes from time.
20 minutes before the goal, Cliftonville's evening was made easier when Glentoran's Darren Murray was sent-off in bizarre circumstances.
As the striker was leaving the pitch, he was shown a second yellow card by referee Steven Gregg.
A new law introduced by FIFA during the summer instructs that players "must leave by the nearest point on the boundary line".
The official had told Murray to exit the pitch on the far side but he ignored that instruction.
"We went down to 10 men and that changed it a lot," Glentoran manager Mick McDermott told BBC.
"When you've got a performance like that from one person on the pitch, pathetic. The game was ruined by one person.
"We're talking about common sense prevailing and trying to upgrade football here, but if one person can ruin a football match like that, then things need to be looked at here."
Sent off while being subbed off😮
A harsh red card or the letter of the law?
Darren Murray falls foul of the new rules about leaving the field of play when being substituted...
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— BBC SPORT NI (@BBCSPORTNI) October 5, 2019