As long as it's a permanent move, no great loss. We need to replace him anyway. He's regularly injured and prone to mistakes. This is his fifth year at the club, he's not established himself as a regular.
Our second string should not be players who are significant level below, they should be players with the ability to push out their first team colleagues, or youngsters with the ability to grow into that. I know that is not always possible, but it's something we should work towards.
Hopefully once we replace him we can replace do the same with Lindelof.