Only United and Arsenal remain in the Champions League for today's draw.
But he told Yahoo!: "Sometimes you get blips. I don't think it is going to be a persistent thing or a consistent thing. I think that English teams will always be challenging to be in the latter stages of the European Cup.
"Certainly Europe over the past couple of years has been disappointing for the Premier League teams, whereas for quite a few years we were getting three teams into the semi-finals - at least two teams.
"We had an all-Premier League final between ourselves and Chelsea so the Barclays Premier League over the past few years has encouraged our teams to do well in Europe."