Klopp brought up a good point after the match again Milan. He said we were too open, and didn't work hard enough to compress the spaces. As a result there was too much space to cover in midfield, even for Fab. That was when we conceded the 2 goals.
I think last season, even when we tried to press and compress the midfield area, we didn't have someone as good as Fab in there to win the ball back for us. We suffered as a result. When Fab came back into the midfield towards the end of the season, we function much better.
That said, i think we should sacrifice a midfielder to bring in another combative midfielder similar to Fab so the drop off wouldn't be that huge when Fab is not available. Anyone of Ox, Keita, even Jones should be sacrifice for someone like Bissouma or Ndidi. That will make us much stronger.