The striker was taking a corner in the second-half in front of the Celtic fans when he picked his nose and wiped it on the flag which had the Rangers emblem on it.
Earlier in the game the 27-year-old blew his nose on blue paper which was part of the Rangers fans’ tifo display prior to the match.
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Griffiths netted the second goal, his 67th in 100 league games for Celtic, in the 2-0 win at Ibrox, extending the club’s domestic unbeaten run to 57 games. Tom Rogic scored the opening goal.