Manager Bruce Bochy indicated Hudson (ankle) is behind on his throwing program due to the offseason surgery on his right ankle, Chris Haft of MLB.com reports.Hudson is considering retirement following the 2015 season, but his potential closing campaign could begin later than expected. It appears he's no guarantee to be ready for opening day because of the issue, as Bochy said Ryan Vogelsong or Yusmeiro Petit could stand in if needed.