"A lot of things were his own fault," former Chelsea and Newcastle United manager Gullit told British media.
"Man United have a certain status ... no Champions League and that's very important for them.
"Football is hard and football is not fair. So you know the rules if you go to big clubs and you don't produce, you're out," added Gullit.
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Former Chelsea and Inter Milan manager Jose Mourinho has agreed personal terms to replace Van Gaal at United, according to Sky TV reports, and the Old Trafford club are expected to rubber-stamp his appointment soon.
(Reporting by Ian Rodricks in Bengaluru; Editing by Tony Jimenez)
