What a dreadful result against the bitter  rivals on Sunday....especially on a day when we were expecting to see the Busby Babes remembered by a stirring display on the pitch.Was this simply a one-off poor performance? Footballers are not robots; Ronaldo, Giggs and Ferdinand do have bad days. We just didn't expect the aforementioned players, along with the other men in Red to show us that on Sunday.It's Arsenal next in the FA Cup on Saturday evening....the beginning of a 5 match period that, for me, will shape Utd's season. The FA Cup, Champions' League 2nd Round home and away vs Lyon; with 2 away matches in the Premier League sandwiched in between.I am a little…just a little…fearful that Utd's poor patch is about to fall at a decisive time in the season and that when we get to the match against Bolton at Old Trafford on March 8th, we could all be a little depressed.That's why I think beating Arsenal in the Cup on Saturday could be crucial and it will send Utd off to France to face the French Champions in a confident mood; ready for an assault on another treble!