FOXBOROUGH — When Bill Belichick and Nick Caserio and the rest of the Patriots’ personnel staff build the roster from season to season, they use extensive research to determine which players they’ll sign and which players they’ll draft.
They have an idea of how each player might perform on the field, and a sense of his personality, but they never really know how the roster will mesh until well into the regular season.
It has to be tested, and how the team survives those tests, the ups and downs of the season — injuries, off-field problems, wins, losses — is shown on a week-to-week basis.
The trials the 2013 Patriots have endured have been well chronicled, and began months ago when receiver Wes Welker departed for Denver in a messy divorce from the team he’d been with for six years. There were multiple surgeries for star tight end Rob Gronkowski, and a murder charge for rising star tight end Aaron Hernandez. Full story for BostonGlobe.com subscribers.