The Black Cats have taken six points from nine since the Italian took charge last month, including a 3-0 win over fierce local rivals Newcastle United last week, but the former Swindon Town manager has played down his role in their upturn in results.
"The commitment from the players is something [that is] amazing," he told Sky Sports News.
"They have completely turned the atmosphere [around] at the club. The players have done brilliantly, so the credit must go to them.
"If you are a good manager and don't have the quality in the team, then you cannot create a miracle."
The win against David Moyes's side moves Sunderland up to 14th in the Premier League.