Brazil international Coutinho has been linked with a summer move to Barcelona, with the Catalan press regularly claiming the 24-year-old is among their top transfer targets and a bid in excess of £50million is being readied.
However, the playmaker only signed a new five-year Reds deal - with no buy-out clause inserted into it - in January and the club are confident they can turn down all offers for their star man in the upcoming transfer window.
Keeper Mignolet is keeping his fingers crossed the former Inter Milan man will be at Anfield for the foreseeable future, saying: "It was a big positive that he signed that new contract. We all hope he stays at Liverpool for many years to come."
Coutinho was deployed in a deeper central midfield role in Sunday's 4-0 win over West Ham and he excelled, scoring twice and setting up Daniel Sturridge for his opener at the London Stadium, and it is a position Mignolet believes his team-mate can really hurt the opposition from.
"In that position he gets more touches of the ball and it worked well," he added to the Liverpool Echo. "They can’t really put one marker on to him. Philippe can distribute the ball in a brilliant way.
"In the Premier League you need creative players to open games up. You look at Chelsea, they have Eden Hazard. Man City have Raheem Sterling, David Silva or Kevin de Bruyne.
"Philippe’s pass put the first goal on a plate for Daniel. That made it a different game. He’s a good boy who works hard. He’s very important to us."