Not only did Miami lose its preseason game against the Texans last night; the Dolphins lost tight end Dustin Keller to a gruesome injury. Keller caught a pass and got his knee mangled by defensive back DJ Swearinger. It immediately looked like it could potentially be season ending.

It turns out it is. Keller has torn his ACL, MCL, PCL, and dislocated his knee in that one instance. He'll miss the entire 2013 season.

Swearinger defended his low hit target by saying he was just trying to play within the NFL's limiting rules: "With the rules in this era you've got to hit low. If I would have hit him high, I would have gotten a fine. So I think I made the smartest play. I'm sorry it happened and I pray he has a speedy recovery...Right now it's just instinct. You see somebody come across the middle, you gotta go low. You're going to cost your team 15 yards. You've got to play within the rules."

It's a shame he has to play by that logic, and unfortunately it led to this gruesome sight.

Keller was a first-round draft pick who previously played for the Jets.

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[via ESPN]