The experienced defender believes the Rossoneri will show their true colours again in Tuesday's curtain raiser at home against Anderlecht
The Rossoneri have lost two out of their opening three league games, but Bonera is adamant that they have shown over the years that they always do well in European club football's premier competition, and is confident they will get back on their feet in Tuesday's encounter.
"The Champions League is an extraordinary competition that is part of our DNA - this could be the game we need at the moment," Bonera said.
"This is a difficult moment for everybody and we must do more, starting with the more experienced players. I think the team has the right quality and that we can be competitive and reach our goals. We just have to become a unit because we have changed so much.
"I don't think we have problems playing at San Siro, it depends on the match. Playing at home should motivate us even more and I don't think it is the stadium that has made us perform badly. We have to prove the supporters right and show that we are not scared of anyone."
Tuesday evening's match at the San Siro is scheduled to kick off at 20:45CET.