The Italian defender believes the starlet will significantly strengthen the Rossoneri, while insisting that the team have greatly improved since the start of the season
The injury-plagued Pato has not seen a minute's action so far this term, as a result of an injury he picked up whilst representing Brazil at the London Olympics.
However, he has since recovered and is expected to make his first appearance when Milan take on Lazio this Saturday, and Bonera believes the attacker rejoins the squad at just the right time.
"It is important that Pato now returns. He is a great player and will definitely be an extra weapon in our attack," he was quoted as saying by Sky Sport Italia.
Massimiliano Allegri's side have been disappointing in their Serie A campaign so far, managing just seven points from seven games. However, Bonera believes that the club have progressed.
"The team have improved a lot. We have had some good games but we've paid for some mistakes," he continued.
"As for the Scudetto? Perhaps not, but the team is getting better and I believe this is clear to everybody."
One area where Milan have suffered this term has been from set-pieces with every one of their goals conceded in Serie A having come from a set-play.
"We have suffered in regard to man-marking. We have not defended the area well from dead ball situations. We have studied where we have gone wrong in previous games over the international break and I believe we are now better prepared," he added.
The former Parma man then recognised Miroslav Klose as Lazio's main threat when the two teams clash, while he blamed a lack of luck as one of the reasons behind the Rossoneri's early season struggles.
"It seems simplistic to just talk about one player. But, Klose is a great individual player. He can be the difference. But, Lazio are a great side, too. You do not get 15 points from seven matches without this being the case," he continued.
"We did not have much luck in the early part of the season. This is one reason why we started so poorly."