By Jamie Spencer Manchester United return to action on Saturday when Brentford, who have made a habit of scoring early goals this season, at Old Trafford. Luke Shaw and Tyrell Malacia are inching ever closer to being available once more, but this weekend has still come too soon for the pair. It means that left-back remains a headache for Erik ten Hag, with Noussair Mazraoui underoing a minor heart procedure and only just returning to training. Mazraoui had been starting games at right-back, but his presence there meant that Diogo Dalot was able to fill in on the left. Now, with Mazraoui perhap…