Patriots running back Dion Lewis returned to practice today, as Ian Rapoport of NFL.com tweets. Now that he has taken the practice field, the Patriots’ 21-day window for activation has begun. 
Lewis was placed on the PUP list in late August as he continued his rehab his knee. Lewis was a key cog of New England’s offense before his ACL tear, rushing 49 times for 234 yards and catching 36 passes for 388 yards. He also scored four total touchdowns, two through the air and two on the ground. After healing up from ACL surgery this summer, Lewis suffered an additional setback in his knee which also required an operation.
With Lewis sidelined, the Pats have leaned on LeGarrette Blount and James White to power the running game. While they have done a capable job for the 6-1 Patriots, a healthy Lewis would give the backfield a major boost.