Naby Keita will become the first player to wear Liverpool's number eight shirt since Steven Gerrard left in 2014.
The 23-year-old midfielder was presented with the shirt by the former Reds captain when the £48m deal to take him from RB Leipzig to Anfield was initially agreed last August.
The Guinea player, 23, who will finalise the transfer on Sunday, said it came as "a surprise".
Liverpool say Keita has signed a "long-term contract" at Anfield.
"It was an incredible day for me. He [Gerrard] gave me the number eight jersey. When it happened, it was a surprise and I didn't expect it," Keita told the club website.
"When he came in, I looked and him and said 'Wow' because he is a legend. He is somebody who always showed respect, who gave his all on the pitch, somebody who is loved here.
"If somebody like that gives you his shirt number, it's not to play around with, it is to try and do as much as he did - that's my motivation."
Keita joins Jurgen Klopp's side after two seasons with Leipzig, where he scored 17 goals in 71 appearances, after the Reds agreed to pay the clause in his contract with the Bundesliga club.
He will join players not currently on World Cup duty for the start of pre-season training at Melwood on Monday, but is already looking forward to improving on Liverpool's 2017-18 season.
"When you see how they performed last season it makes me want to do the same and to be a part of this team. I would like to be able to achieve a similar kind of season with them - but even better."
Liverpool were beaten by Real Madrid in the Champions League final in May and finished fourth in the Premier League.