The full-back will join Roma from Ajax today after landing in the capital on Wednesday.
Rensch will move to Roma for six million euros and agree on a contract until 2029.
During yesterday's Europa League preview before their match against AZ Alkmaar, Ranieri said: “He has no physical strength but he has great timing when it comes to insertion, good foot both right and left, he needs to improve but I think like him.” and I am sure he will give us great satisfaction.”
Ranieri also said about tonight's draw: “I am sensitive because I always want to win. It will be tough, it is a young team that is going in transition at 3000 per hour, we expect a great performance and I am curious to see how we will respond.
“The team is doing well, they are motivated, they are doing well. I am sure we will play a great match.”