I couple of losses and draw at the start of the season aren't enough reasons to sack Mou so I think Man Utd will keep him around until they're actually in a bad spot (like middle of the table). Same thing I said about Poch a few posts above apply here as well, you simply don't have top managers looking for a job, let alone to take over a big team like Manchester United.

There are some rumours about Man Utd getting interested in Zidana...IMO i don't think Zizou is ready to be the manager, one thing is Real Madrid, where he had all the support in the world from the fans, the players, and board of directors, and most importantly, the president Florentino Perez, another different thing is Manchester United, where he will start from 0 (I don't even think Zidane knows how to speak in english lol) without having the massive support and trust from the people around him.

As long as the team doesn't start a losing streak or doesn't do well in the Champions League, Mou will stay. The only reason why they would sack him would be because of some internal issues with the board of directors or with Ed Woodward, otherwise, he'll stay. I consider Mou a top manager, and I believe sooner or later he will fix things up.