Roma chief Walter Sabatini admits they need to get tighter at the back.

Roma defeated Champions League opponents Bayer Leverkusen 3-2.

Sabatini said, “The statistics say we're good going forward and a little shakier at the back. We made certain choices on the market because we expected Leandro Castan to be back quickly and he is, but he is taking longer to reach full form.

“Kostas Manolas is a guarantee, then we got this 23-year-old German international Antonio Rudiger, whose performances have been light and shade."