Robin van Persie's hat trick in Wednesday's contest with Olympiakos was enough to send Manchester United into the Champions League quarterfinals after the Red Devils fell behind 2-0 after losing the first leg in Athens.

For one night, at least, the fans at Old Trafford could forget the many disappointments they have had to endure this season.

United faced Olympiakos just days after a crushing 3-0 home loss to archrival Liverpool that left the Red Devils 12 points out of the fourth and final qualifying spot for the 2014-2015 Champions League.

David Moyes, under fire for the team's mediocre performance in the Premier League, made some changes to the starting lineup, inserting Danny Welbeck and Antonio Valencia up front and 40-year-old stalwart Ryan Giggs to anchor the defense.

The Spaniards guarding the respective goals, United's David De Gea and Roberto Jimenez of Olympiakos, both made a pair of key saves in the first half and it took a mistake to break the match open.

Olympiakos defender Jose Holebas ran into Van Persie in the area and the Dutch international beat Jimenez with a virtually unstoppable shot.

The home side still trailed 2-1 on aggregate until the 45th minute, when Van Persie connected again on a pass from Wayne Rooney.

What turned out to be the winning goal came just six minutes into the second half, when Van Persie sent a free kick sailing over the wall of Olympiakos players and past Jimenez into the net.

Borussia Dortmund, last year's Champions League runner-up, advanced to the quarterfinals despite losing Wednesday's second leg 2-1 to visiting Zenit St. Petersburg.

Dortmund won 5-4 on aggregate, but will be without striker Robert Lewandowski for the first leg of their quarterfinal contest.

The Polish international must serve a one-match suspension for an accumulation of yellow cards, the latest of them for an inadvertent hand ball in Wednesday's clash. EFE