Rob Gronkowski is no stranger to an injury. It was a back injury in college that allowed him to fall to the New England Patriots in the NFL draft, and it has been back and arm injuries that have kept him from reaching his potential as the most consistently dominant tight end of his era. Now, it looks like it will be a knee injury that keeps him from being the weapon the Patriots need down the stretch to contend in the playoffs. After making an over-the-shoulder catch on one of his patented seem routes, Gronkowski was hit low by Cleveland Browns defender T.J. Ward and immediately grabbed for his knee. We don’t yet know the severity of the injury, but before being carted off the field, members of both teams went out of their way to offer their support to the popular player, something that is never a good sign. If, and it is a big if, Gronkowski has seen his last time on the field for New England this year, the Patriots’ season is effectively over. Despite sleep-walking through the last few weeks, the New England fans had still been hoping that the team would wake up for the playoffs, much like they did against the Denver Broncos in the second half just a couple of weeks ago. Gronkowski is the weapon Tom Brady and the Patriots need to kick-start an offense that has struggled all season, especially earlier in the year when he was on the sidelines. Gronkowski is a matchup nightmare for defenses, and his presence alone opens up room for the diminutive receivers on the New England roster. Without him on the field, the Patriots don’t have the kind of firepower they will need against the better teams in the AFC. Ben Sullivan is an NFL writer for RantSports.com. Follow him on Twitter @bensullivan52, “Like” him on Facebook and add him to your network on Google.