Impressive debuts have been all the rage at Manchester United recently. There was Noussair Mazraoui and Joshua Zirkzee in that 1-0 victory over Fulham in the Premier League’s curtain raiser. The former excelling at right-back and the latter turning home an Alejandro Garnacho cross to mark his Old Trafford unveiling with an 87th minute winner. Though an eye-catching start is not merely limited to those who have arrived at Manchester United. Mason Greenwood scored twice on his Ligue 1 bow for Marseille. Aaron Wan-Bissaka stepped off the bench and helped set up Thomas Soucek’s game-breaker in the…