Liverpool were fined 200,000 pounds for fielding an ineligible player in their League Cup third-round victory over MK Dons last week.
The Reds, however, avoided expulsion from the competition, the Football League (EFL) said on Wednesday.
Spaniard Pedro Chirivella, who was a second-half substitute in the 2-0 win, did not have international clearance, following the expiry of his loan agreement last season with Spanish club Extremadura, the EFL said.
Half the fine will be suspended until the end of the 2020/21 season and the club will be liable for the suspended amount if they field an ineligible player in the competition again before the end of the next season.
“Following a comprehensive review of all the evidence, the board determined that it wasn’t appropriate to expel the club from the competition because of a number of mitigating factors,” the EFL said in a statement.
The EFL said Liverpool had asked the Football Association for assistance in securing international clearance before the season and the 22-year-old midfielder was also included on team sheets for Premier League Two matches and an EFL Trophy game.
The breach was not identified until the Anfield club reported it to the EFL and the Premier League after the 2-0 victory over MK Dons, leading to a misconduct charge.