The New England Patriots saw key players who were injured last season return to the practice field for OTA's on Thursday.Logan Mankins, Rob Gronkowski, and Vince Wilfork were all on the field and participating in practice for the first time this off season. All three players suffered season ending injuries last year and their return has in encouraging for a team that played much of 2013 with a depleted roster. While neither of the three are considered game ready, they have received medical clearance to take part in some practice drills.