McDermott was a fixture in the 1977 side that retained the title. Meanwhile, his goal against Everton in the semi-final of the FA Cup, a turn and chip from the edge of the penalty area, was voted the 'Goal of the Season' by the BBC. That game finished 2–2, with Liverpool winning the replay. A subsequent success in a European Cup semi-final meant that Liverpool had reached the finals of both the FA Cup and European Cup, which were scheduled to be played respectively at Wembley and at Rome's Stadio Olimpico within four days of each other in May 1977. However, Liverpool were defeated in the FA Cup Final by Manchester United, which ended their "treble" dream. There was joy for McDermott four days later, though, when he opened the scoring in the European Cup Final against Borussia Mönchengladbach as Liverpool won 3–1.