Liverpool manager Jurgen Klopp has revealed the switch in his side's formation was made to get the best out of midfielder Fabinho.
Playing alongside Georginio Wijnaldum, the Brazilian was part a double pivot with both men deployed with the intention of creating a defensive platform as well as linking midfield and attack when transitioning the ball up the field.
Despite the goals coming from Mohamed Salah, Roberto Firmino and Sadio Mane, Klopp was keen to point out the quality of Fabinho’s performance - which included nine successful tackles.
Speaking after the game, Klopp revealed his happiness in regards to Fabinho. He said, as quoted by the Liverpool Echo: “Very good, very, very good.”
The former Borussia Dortmund manager then expanded on the formation change, saying: “The present for his birthday was not that he was in the starting lineup, it was that we played his favourite system with a double six [two holding midfielders].
“He played really well. It was good to see. Very aggressive - everything was there. For the first game in a while, his second game from the beginning, it was good."
Klopp finished by expressing his hope that the performance would be the start of something good for his new holding midfielder.
He added: “It was quite impressive what people saw tonight. It always helps a player to play a good game, and that helped us tonight and helped him. That was the start, let’s carry on.”
Regardless of the new system, positions were fairly flexible in the attacking third. The Liverpool forwards interchanged constantly as they unpicked the Red Star defence throughout the night.
Liverpool now sit at the top of their Champions League group - which includes both Napoli and PSG, who played out a 2-2 draw in Wednesday's clash. They face Red Star Belgrade again next, this time away from home.