49ers' Patrick Willis out for preseason with broken hand
The report also states that the team will "proceed with caution" in keeping Willis out of preseason action.
CSNBayArea.com reported that Willis wore a wrap on his hand after suffering the injury from a collision during a blitz pickup drill. The six-time Pro Bowler had 88 total tackles and 2.5 sacks last season for the Niners. VIDEO: Postcards from training camp