Complex sentence: New coach Allegri kept him in the same position for the 2010--11 season where he was a starter throughout and his solid defensive performances lent a hand in winning Milan their 18th Scudetto and the Super Coppa Italiana.
Split into simpler sentences: New coach Allegri kept him in the same position for the 2010--11 season. His solid defense has also lent a hand in winning Milan their 18th Scudetto and the Super Coppa Italiana.