The Argentina international, who lifted the World Cup at the end of last year, completed a £35million move from Brighton to Merseyside on Thursday morning.
Although prices as high as £65m had been quoted for the 24-year-old, a release clause in his contract – which was only signed shortly before the World Cup – allowed him to leave for the bargain fee.
Surprisingly given the modest fee, Liverpool had a relatively free run at Mac Allister – though very nearly experienced a late hiccup.
According to The Times, new Chelsea boss Pochettino made a late swoop for his compatriot before Liverpool had managed to rubberstamp the deal.
But by this point Mac Allister had already given his word to Liverpool and he was eager to work under Jurgen Klopp, while the Reds will also be competing in Europe unlike Chelsea.
Missing out on the Argentine adds to what is already starting to feel like a frustrating summer for the west Londoners, who were also gazumped by Paris Saint-Germain in the race to sign Sporting’s Manuel Ugarte.
Chelsea are now thought to be targeting a move for another Brighton star, Moises Caicedo, though the relatively modest fee for Mac Allister means the Seagulls will look to make up for that shortfall by demanding in excess of £80m for the Ecuadorian.
Speaking about his move to Liverpool after it was confirmed on Thursday, Mac Allister told the club’s official website: ‘It feels amazing. It’s a dream come true, it’s amazing to be here and I can’t wait to get started.
‘I wanted to be in [from] the first day of pre-season, so it’s good that everything is done. I’m looking forward to meeting my team-mates.
‘It was a fantastic year for me – World Cup, what we achieved with Brighton – but now it’s time to think about Liverpool and try to be a better player and a better human being every day.’
He added: ‘Since I won the World Cup, I said that I want to win more trophies and I think that this club will help me to do that – that’s the aim and when you are in a big club like this one you have to win trophies. So, that’s what I want.
‘Since I arrived here, I can see how big this club is – the players we have, the staff, everyone. I’m really pleased and looking forward to playing for this club.’
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