Benteke, 25, scored 49 times in 101 games during his three seasons at Aston Villa before securing a £32.5 million move to Liverpool last summer, but he has so far failed to reproduce that form in a red shirt.
The Belgian striker has struggled to hold down a regular place in the line-up after scoring just 10 goals in 40 total appearances and spent all of last month on the sidelines with knee ligament damage.
It is now being rumoured that manager Jurgen Klopp will look to sell the former Genk forward in the summer, with reports this week suggesting that West Ham United are poised to make a £25 million bid for his services [h/t Mirror].
Nevertheless, Mignolet does not see Benteke leaving the club so soon, and having been using his experience to help him through his tough time, he expects his compatriot to come back stronger next term.
"He just has to work hard and keep his confidence because he's got all the ability needed to play at Liverpool, so it will come,” Mignolet told the Mirror. “He needs to be patient and to work hard off the pitch, and if he does, that will be paid back on the pitch.
"It's not easy as a striker coming from club like Aston Villa, where he was the big star and everyone had a lot of confidence in him.
"He has come to a club like Liverpool where first he has to fight for his place in the team, where there are different players with the same abilities and different kind of styles to him.
"When you get injured, like he did, it's difficult to get going. You need a bit of time. But I know what kind of character he is. He will always keep his head down and work hard."
In the meantime, Benteke managed to earn some plaudits in midweek after coming off the bench to bag a stoppage-time equaliser against Chelsea, keeping Liverpool’s slim hopes of a top-six finish alive ahead of their Premier League finale at West Bromwich Albion.
The physical front man previously scored in the 3-1 loss at Swansea City earlier this month before grabbing an assist in last weekend’s 2-0 home win over Watford, and Mignolet believes his recent form shows he is starting to adjust to life at a big club.
"It's a constant battle to prove yourself here," Mignolet told the Mirror. "You can never think you've done it. If you play for Liverpool, you have to show up every game you play. That's just the way you have to see it.
"You can't get carried away with a good performance. You can't get too down after a bad one. You have to keep your head and it's not only what you have to show on the pitch, there's so much more that comes with the territory. You're not just football player, but a role model too."