McFarlane lived in the London Borough of Hackney. He started out as a schoolboy winning the English schoolboys' 200 metres on three occasions. This success continued as he went on to win the AAA's junior Indoor 60/200 metre titles. This was followed by an outdoor AAA's junior 200 victory. He was also a South of England Champion and in 1979/1980 he won the European junior and AAA's Indoor 200 metre titles.
In 1980, he went to the Moscow Olympics where he ran in the 200 metres, where he got to the quarter-final. He was also a member of the sprint relay team that reached the final and finished fourth in a new British record. In 1982, after winning the U.K. championships 200, he went to his second Commonwealth Games where he won a joint Commonwealth gold alongside 1980 Olympic 100-metre champion Allan Wells in an historic and memorable 200 metres where both men could not be separated, and both claimed gold medals.[1]
In 1984, he won the U.K. championships 100 metres, then went to the Los Angeles Olympics where he reached the final of the 100 metres, and finished in fifth place. In 1985, he became European Indoor Champion at 60 metres. In 1986, he competed at his third Commonwealth games where he won bronze in the 100 metres, and silver in the sprint relay.[2][3] He also reached the European 100 metre final in Stuttgart in 1986 where he finished 6th. He ran in the 100 m at the 1987 World Championships in Athletics, failing to make the final.
McFarlane competed for Great Britain in the 1988 Summer Olympics held in Seoul, South Korea in the 4 x 100 metres relay where he won the silver medal with his teammates Elliot Bunney, John Regis, and Linford Christie. He subsequently made a successful career in coaching after retirement and was a high performance coach for UK Athletics based at the National Athletics Centre in Lee Valley.