The Chelsea loanee has impressed during his stint at The Hawthorns and has scored 10 goals so far this season, including one when the Baggies defeated Sunderland 4-2 at the Stadium of Light in November.
With that in mind, Mignolet has warned his defenders that they will need to be on their guard against his fellow Belgian.
"He's a very good player and I've known him since he was very young playing for Anderlecht in Belgium as well," Mignolet told the club's official website. "He is very strong, very quick and can score goals. Hopefully he won't do that on Saturday.
"He's been around since he was 17 as well, people know him now hopefully our defenders will be up for it on Saturday."
Sunderland go into the match 13th in the Premier League table.