The Reds were 2-0 winners in the first leg of their Europa League last-16 clash last week thanks to goals from Daniel Sturridge and Roberto Firmino.
Sakho started alongside Dejan Lovren at the heart of the Liverpool defence, whilst Origi was a second-half substitute at Anfield.
But the Liverpool trio presumably brought their children along to the birthday party of Lucas Leiva’s son on Monday night.
Origi wrote: “At @leivalucas sons birthday party yesterday 🎉🎊”
United are unbeaten in ten European home games (W8 D2), and have recovered from a 2-0 away defeat to win a European tie more than once, perhaps most notably beating Barcelona 3-0 at Old Trafford in the 1983/84 European Cup Winners’ Cup quarter-finals after a 2-0 first-leg loss.
Liverpool kept a fourth successive clean sheet in the first leg – one more in the second leg and they will match SSC Napoli’s Europa League record for successive games without conceding.
Liverpool – along with AC Sparta Praha, SS Lazio and round of 32 entrants FC Shakhtar Donetsk – are the only surviving sides yet to lose in this season’s Europa League proper. The Reds have drawn five of their nine games since matchday one, more than any other side in the competition.
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