Karius turned down an opportunity to represent Germany at the Rio Olympics this summer in a bid to press his first team claims at Anfield, before a broken hand ruled him out of the opening month of the campaign anyway.
The German is now fully recovered and set to return to training, but Mignolet is relishing the challenge ahead.
“When I signed that new contract the club said that there would be fresh competition," he explained. "That is the normal thing - that you have three competitive goalkeepers.
“Besides Karius we also have Alex Manninger and all three of us get on well. I have already learned a lot from Alex. He is someone who has worked throughout Europe and gives me a lot of confidence."