The young defender has agreed a new deal at the club after fighting back from injury.
The Liverpool defender has recently fought his way back into the first team setup having been absent since picking up a serious knee injury at the end of the 2013-14 campaign.
He has been warmly welcomed back into the fold as well having played a big part in the season that saw Brendan Rodgers side finish second in the Premier League behind Manchester City.
And Mignolet has praised his hard work in fighting back from that layoff, saying he is sure he can help the team in the future.
"All credit to him because he’s worked really hard in his rehab to come back from injury," he told Liverpoolfc.com.
"I think in the few games he’s played [since returning] and in training sessions he’s [shown] he is a really good defender, he’s got that aggressiveness, and I’m sure he can help the team in the future.”
“I hope he stays injury free and can continue - because he’s only young as well – the way he is at the moment because he’s a very good player and he can definitely help us out."
It will now be interesting to see where Flanagan can fit into the side under Jurgen Klopp.
Right back is arguably his most natural position, but Nathaniel Clyne, who has impressed in the role since joining from Southampton, currently occupies that role.
Left back may be a more suitable location for him, with Alberto Moreno having struggled to impress in the position on a regular basis under both Klopp and Rodgers.