كتب : Amro Hassan
Isla's strike was scored 13 minutes from time, to maintain Inter's place at top of the table and move Jose Mourinho's men one step closer to winning the league title.
The performance was nowhere Inter's best, and the visitors were lucky to be helped by Isla's error.
The Nerazzuri were also aided by Juventus' slip, after The Old Lady were held to a 3-3 draw by Chievo Verona earlier on Sunday.
Inter are now on 72 points, nine clear of second-placed Juventus.