Rickie Lambert has completed his move from Saints to Liverpool.
The 32-year-old striker was this morning confirmed as a Reds player, signing a two-year contract with his boyhood club.
The deal is worth as much as £5m, plus add-ons, for Saints, although Lambert's former club, Bristol Rovers, have a 20 per cent sell-on clause.
Lambert, who has thanked Saints fans in an open letter, said: "I can't believe it. I've loved this club all my life. I left here 17 years ago - and I haven't stopped loving it since.
"I have always dreamt of playing for Liverpool, but I did kind of think the chance of playing for them had gone. I didn't think the chance would come.
"I know how big Liverpool are - and it means everything to me - but I know what is important; I know it's what I do on the pitch and the minutes I play. I know that's what matters, and that's what I'll be focused on."
Liverpool, who released Lambert as a schoolboy, moved for the player last Thursday.
Last season's runners-up in the Premier League said a deal for him would have to be done before the World Cup, or not at all, with Saints feeling it could do more harm than good to deny the forward his dream transfer.
The deal marks the end of an era at St Mary's, with Lambert having established himself as one of the club's most influential players of recent times.
He joined Saints from Bristol Rovers in 2009, helping the club rise up from the depths of League One to the top half of the Premier League.
He made 235 appearances during his five years at St Mary's, scoring 117 goals.