Olympiakos' Joel Campbell celebrates after scoring against Manchester United during their Champions League round of 16 first leg soccer match at Karaiskaki stadium in Piraeus, near Athens, February 25, 2014. [Photo/Agencies]

PERIPHERAL FIGURES

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Strike pair Wayne Rooney and Robin van Persie were peripheral figures for the visitors as pot shots on goal from Giannis Maniatis and Hernan Perez lifted the home supporters.

Olympiakos, wearing red and white jerseys, red shorts and socks, broke the deadlock seven minutes before halftime with a clever piece of improvisation from Argentine forward Dominguez.

Patrice Evra's half-hearted clearance from a corner landed at the feet of Maniatis 25 metres out and his tame, low shot was expertly diverted past keeper David De Gea by Dominguez's flick.

United, the European champions in 1968, 1999 and 2008, were punished again for poor defending 10 minutes into the second half.

Campbell, who is likely to feature for Costa Rica against Group D rivals England at the World Cup in Brazil in June, did the damage.

He picked up possession 25 metres out, jinked past midfielder Michael Carrick and sent a curling left-foot shot around defender Rio Ferdinand and into the bottom corner of the net.

Moyes sent on Danny Welbeck and Shinji Kagawa for Valencia and Cleverley but it was more a change in attitude than personnel that was required from United.

Dutch striker Van Persie summed up his team's night with five minutes to go. He received the ball 12 metres out and turned inside a defender before blazing a right-foot shot way over the bar.

"We had good possession in the first half and were controlling the game without really penetrating and causing them any problems," said Carrick. "But at the same time they weren't causing us any problems and the goals came from nothing.

"We didn't start the second half very well, we were a bit sloppy really, and they scored the second goal which put us on the back foot."