December 21, 2006 — MGM's "Rocky Balboa" proved no underdog at the boxoffice its opening day. The Sylvester Stallone-starrer reaped an estimated $6.2 million on 2,752 theaters. The PG-rated boxing tale generated a per-screen average of $2,267 for its first day in the theaters. The film will expand to 3017 theaters on Friday. Click the link below to read on.