Slaven Bilic: English sides can underestimate UCL opponents

English clubs suffer disappointing Champions League results because they underestimate their opponents too often, West Ham manager Slaven Bilic believes.

Speaking after a week in which Manchester United lost at PSV Eindhoven and Arsenal were beaten at Dinamo Zagreb, the former Croatia boss said teams could be taken too lightly.

Bilic, who was in charge of the Besiktas side that beat Liverpool on penalties in the Europa League last season, said: "Why are people so surprised when Manchester United lose a game against PSV?

"It isn't a shock, and you have to know that the other teams are also good.

"Many big clubs have lost at PSV -- they were European champions once."

He also hit out at reaction to Arsenal's defeat in Croatia, saying: "You can lose in Zagreb. It was a major surprise -- the whole of Croatia was surprised -- but it can happen.

"They play football there as well. They are a decent team, unbeaten in 41 games or whatever."

Manchester City were beaten at home by Juventus, and only Chelsea bucked the trend this week, notching up an easy 4-0 home win over Maccabi Tel-Aviv.