Other than a brief spell of Morton pressure early in the match, Celtic enjoyed the kind of dominance in the Scottish Cup tie they have regularly had in league games this season.
With Kyogo Furuhashi scoring twice and moving on to 20 goals for the season, the striker was given the second half off. Liel Abada, who had played a part in the first four goals, was also rested for the end of the match.
Aaron Mooy’s influence in the team continues to grow with a well struck penalty for the opener and a late strike make it 5-0, while David Turnbull netted his second goal in two games to bolster his first-team chances.
With a nine-point lead in the Premiership, a place in the Viaplay Cup final against Rangers and now a berth in the Scottish Cup last-16, the treble is very much on for Ange Postecoglou’s side.