Senegal forward Sadio Mané is one of 368 players in Gabon for the 2017 Africa Cup of Nations, 23 of them from the EPL. Having cost Liverpool £35 million ($43 million) when he signed last June, he is the most expensive footballer on show at the tournament.
And, unfortunately for Klopp, the 24-year-old could be absent for as many as eight games -- including both legs of the League Cup semifinal tie against his former club Southampton, as well as vital clashes against rivals Chelsea and Manchester United -- if his country reaches the February 5 final.
Liverpool's win ratio with Mané in the team is 70%, and just 50% without him.
With nine goals and four assists in 19 appearances, he's directly contributed to more league goals than the likes of Chelsea's Eden Hazard, Manchester City's Sergio Aguero and last season's golden boot winner Harry Kane of Tottenham.
Klopp has addressed the problem saying, "We can do things, change systems" -- but what do the stats say about Liverpool's performances with and without the most expensive African footballer of all time?
Eighth in the table last season after Klopp took charge in October 2015 -- below the likes of West Ham and Southampton -- the Reds have rallied this campaign and occupied second place behind Chelsea before being held 1-1 away to fierce rival Manchester United on Sunday and dropping to third on goal difference.
No team has lost fewer matches -- second-placed Tottenham also has two defeats.
While fellow summer signings Georginio Wijnaldum and Joel Matip -- who turned down the chance to play for Cameroon in Gabon this month -- have also had a hand in making Anfield a fortress once again, neither has been so integral to Liverpool's success as Mané.
The former Metz and Red Bull Salzburg striker has completed 47 take-ons -- more than twice as many as teammate Adam Lallana -- and created 33 chances, second only to Roberto Firmino.
With the third-highest performance score in CNN Sport's ROI rankings
, Mané's presence has helped Klopp's side to 14 wins, five draws and just one loss.
Mané didn't taste defeat until his 14th competitive Liverpool match -- and even then through no fault of his own, with the Reds 3-1 up against Eddie Howe's Bournemouth when he departed the field for Lallana in the 69th minute.
The rest is Cherries history -- Bournemouth rallied to win 4-3 -- but with a goal and an assist to his name, Mané could have been forgiven for heading to the bench thinking the job was done.
Liverpool's only other Premier League setback this season was August's dismal 2-0 defeat at promoted Burnley, and Mané was similarly sidelined when it all went wrong.
Burnley had just 19% of possession -- the lowest proportion from a winning team since records began in 2003 -- but still did enough to triumph 2-0.
Mané's pace and ability to break between the lines was missed -- something clearly encapsulated by Southampton's struggles in front of goal since his departure. The Saints have only scored 19 goals this season -- fewer than many teams in and around the relegation zone.
Without Mané in the squad, his Liverpool teammates have struggled, losing 33% of matches.
"We knew before it's part of the deal," Klopp admitted. "We get this outstanding player who unfortunately won't be involved in January.
"We cannot change the football in this moment. Sadio is away; we need to find solutions."
Mané admitted "it will not be easy to go with Senegal" after scoring the winning goal against Everton in December.
"I would love to carry on playing with my teammates and help my team, but I think they will understand because it is my country and it is my dream."
He scored in his last game before leaving Gabon, a 2-2 draw with struggling Sunderland on January 2, and since then Liverpool has been held 0-0 by fourth-tier side Plymouth in the FA Cup and lost 1-0 to Southampton in the first leg of the League Cup semifinal before the January 15 draw at Old Trafford.
Mané was Senegal's top scorer with three goals as the "Lions of Teranga" won all six AFCON qualifying matches -- and made the perfect start to this month's tournament in Gabon
with a penalty in Sunday's 2-0 win over Tunisia.