The likes of Mohamed Salah, Alex Oxlade-Chamberlain, Daniel Sturridge and James Milner were among those taking part in the morning session, as well as Andy Robertson after returning from the Scotland camp.
Those Reds players who are still with their countries will continue to arrived back at Melwood over the remainder of the week to get ready for Saturday's Saints showdown, while Jürgen Klopp confirmed on Monday that Sadio Mane will also be heading back to Merseyside on Tuesday.
Browse our gallery from the club's training complex below now.
Photos by John and Andrew Powell
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