The 26-year-old underwent a medical at the Reds’s Melwood training ground after Southampton accepted a reported £25m bid for the England international.
It got the hairs on the back of my neck standing up just watching them
And Lallana, who has signed a long-term Liverpool deal, admitted he wanted to play in the Reds side after watching their end-of-season form.
“Watching the run-in towards the end of last season was unbelievable, not just for myself but everyone involved in football,” Lallana told Liverpool’s website.
“It got the hairs on the back of my neck standing up just watching them, and the style of football they were playing. Deep down, I was thinking to myself: hopefully one day I’ll be able to play in that team.
“That dream has become a reality now, so I can’t wait for that to get started.”
And Lallana vowed to help the Premier League runners-up go one better next season and win silverware under manager Brendan Rodgers.
“Hopefully I can settle in quickly, and I will give it my best throughout the whole time I’m here,” Lallana added.
“I hope I can add something to the team and hopefully we can win trophies while I’m here, because that’s why I’m here – for success.”
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