By Steve Bates Erik ten Hag called for patience for his young stars and claimed even great Manchester United teams needed time to grow after a disappointing draw against Burnley. Boos echoed around Old Trafford after Zeki Amdouni scored an 87th minute penalty to cancel out an Antony goal that had seemed to put United on course for victory. United’s Dutch boss acknowledged the fans frustration, especially after substituting Kobbie Mainoo earlier in the second half, but pleaded for time as his stars squandered another winning position. “We are building this club back with young players and that …