They arrived in the offseason at a combined cost of $140 million, with the intention of bringing a new dimension to Liverpool's midfield.
Fabinho would be the pure, out-and-out holding midfielder the team had been missing for a few years. Naby Keita would be the energetic, goal-scoring, box-to-box runner in the mold of Steven Gerrard.
It has taken eight months — and some initial skepticism — but they are finally proving their worth to a team that could yet end the season as the Premier League champions, not to mention Champions League winners.
The goals from Liverpool's three-pronged strikeforce of Mohamed Salah, Sadio Mane and Roberto Firmino speak for themselves. The defense, marshalled by the dominant Virgil van Dijk, is deservedly getting plaudits for the being the meanest in the league.
But Liverpool manager Juergen Klopp at last might have his ideal midfield to complete the team.
Much to his initial frustration, Fabinho was eased slowly into English soccer by Klopp following a move from Monaco for 50 million euros ($58 million). The Brazil international has underlined his versatility by filling in at center back — and even right back — but is now a mainstay as the team's midfield anchorman, his long legs and reading of the game regularly breaking up opposition attacks.
Keita has taken even longer to feel at home since joining from Leipzig for a reported 70 million euros (then $85 million). Some turns and flicks aside, the Guinea midfielder has produced largely forgettable performances in his first season for Liverpool as he struggled to get attuned to the pressing game required in Klopp's team.
But he has started Liverpool's last three games and scored in two of them — his first goals for the club. Even though he didn't score in the 2-0 win over Chelsea on Sunday that kept Liverpool in first place by two points, Keita regularly popped up in or around the box to give Chelsea's defenders another player to think about apart from Mane, Salah and Firmino.
"It is not easy to move from Germany to change club, especially as the league is not the same," said Mane, who briefly played with Keita at Red Bull Salzburg in 2014. "It is part of the things you have to deal with and he is working hard every single day.
"The real Naby is coming still."
Tellingly, the blossoming of Fabinho and Keita has given Jordan Henderson some license and freedom to get forward, and the captain is in arguably his best form this season. Henderson changed the game when coming on as a substitute in the 3-1 win over Southampton on April 5 and set up Mane's opening goal against Chelsea with a delicate cross after bursting into the box.
Henderson recently revealed he went to Klopp's office to speak to the manager about playing further forward, having spent most of the season as the holding midfielder in front of the defense. Fabinho's emergence has enabled Klopp to make that switch and Henderson looks, for the moment anyway, to have ousted Georginio Wijnaldum from the lineup.
It is a tough call on Wijnaldum, who has been one of the best players not just for Liverpool but in the Premier League.
But these are the ebbs and flows of a long season and the Fabinho-Keita-Henderson triumvirate looks to be Liverpool's new-look midfield. Expect them to be first choice for the final games of the season as the team chases titles at home and in Europe.
Steve Douglas is at www.twitter.com/sdouglas80