After being part of the winning Wales team in the first two snooker World Challenge Cups, in 1979 and 1980, he had an attack of Bell's palsy which partially paralysed his face. With the problem cleared, he reached the final of the 1981 World Championship, defeating Eddie Charlton, Dennis Taylor and, in the semi-final, Ray Reardon (against whom he made a 145 break, a championship record at the time). He then played Steve Davis in the final. Davis was favourite to win his first world title, and appeared to be racing to an easy victory by winning the first six frames of the match. However, Mountjoy recovered and came close to drawing level on several occasions. Trailing 11–13, and with the score at 60–63 in the 25th frame, he looked certain to cut Davis's lead to one frame but missed a simple blue from its spot; Davis went on to clear the colours, fluking the final black. Mountjoy won only one more frame as Davis eased to an 18–12 victory.