Here Press Association Sport looks at the Reds’ raids on St Mary’s and how they have fared at Anfield.
The big striker was bought as a back-up to provide a Plan B but he never suited then manager Brendan Rodgers’ system and while his story of returning to a club which released him as a youngster was heart-warming, only three goals in 36 matches (most as a substitute) underlined the mistake.
Sold to West Brom in 2015 for £3m, the striker has recently retired.
The England international’s acrimonious departure from Saints did not help his settling-in process and an injury in pre-season delayed his debut – but under Jurgen Klopp he has shown the form that has made him one of the stand-out midfielders in the Premier League.
His current campaign has been blighted by injury, however.
The centre-back was brought in to provide some much-needed leadership following the retirement of stalwart Jamie Carragher but the Croatia international initially struggled with the responsibility.
His form at the start was patchy, but, although a gaffe never seems far away, he has improved markedly.
Arrived as first-choice right-back and produced consistent, if not spectacular, performances in his maiden season which took him into the England squad for Euro 2016.
Backed that up last season but suffered a back injury in the summer and has yet to play this time around.
The Senegal international proved to be money spent well as he enjoyed a fine start to life at Anfield, so much so that his departure to the African Cup of Nations was blamed for Liverpool’s January blip.
He ended the campaign with 13 Premier League goals in 27 appearances and has followed that up this season by becoming one of the feared ‘Fab Four’ – alongside Philippe Coutinho, Roberto Firmino and Mohamed Salah.
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