The New England Patriots were missing pretty much their entire 2015 offensive line in the first open practice of 2016. Left tackle Nate Solder wasn't there, and neither was right tackle Sebastian Vollmer. The guard trio of Josh Kline, Shaq Mason, and Tre Jackson were not present.
Swing tackle Marcus Cannon was not reported missing (insert your own jokes here), and both centers Bryan Stork and David Andrews practiced- and both ESPN's Mike Reiss and the Herald's Jeff Howe believe that Stork and Andrews have an equal shot of winning the starting role.
Solder's absence isn't crazy because he's recovering from his torn biceps last season. Jackson is recovering from a knee surgery, and Mason battled knee injuries of his own last year. I'm sure Vollmer has his own reasons- he sprained his ankle late in the season and had a long list of his own injuries.
Howe reports that Kline's absence is linked to his shoulder injury that caused his sharp decline in play over the course of the season. "It's unclear when he'll be ready to practice," Howe adds.
Kline was the Patriots best offensive lineman in 2015, before he injured his shoulder and became yet another weak spot. Hopefully he recovers quickly because the offensive line needs all the help it can get.