Watford were unable to make their dominance count during the first half at Loftus Road as the contest with QPR remained goalless at half-time.
QPR had to wait until the quarter of an hour mark for their first chance, a tame Charlie Austin shot, and then another 15 minutes for their second effort; this time Danny Simpson’s volley made Manuel Almunia work marginally harder.
It was all Watford in the opening half an hour as they controlled possession with composed yet incisive play.
Troy Deeney forced Robert Green into a decent save from 18 yards and the Watford striker and Daniel Pudil both would have got shots away in the box had it not been for last-ditch challenges.
McGugan and Deeney also had wayward efforts from distance during a dominant period of play from the Golden Boys.
Rangers came into it a bit more as the break approached but the visitors’ defence was rarely troubled.
Former Parmiter’s School pupil Tom Carroll struck a free kick which Almunia had to parry clear but it was a routine stop for an experienced goalkeeper.
QPR line-up: Green; Dunne, Onuoha, Hill; Simpson, Carroll, Barton, Traore; Morrison; Doyle, Austin.
Subs: Murphy, Yun, Hughes, Henry, Hoilett, Zamora, Keane.
Watford line-up: Almunia; Angella, Cassetti, Ekstrand; Riera, Abdi, Tozser, McGugan, Pudil; Deeney, Ranegie.
Subs: Bond, Battocchio, Merkel, Doyley, Murray, Faraoni, Hoban.
Referee: James Linington.