Long dealt with a bad left knee all season last year, before a back injury, and ultimately, a torn biceps muscle put the 2008 number one overall draft pick on injured reserve. Up until last season, Long had never missed a start in his career. Long's left knee was injured near the end of the 2010 season.
Long came in to this preseason saying he was the healthiest he had been on a long time. He is expected to return to his normally dominant level, and is set to anchor an upgraded Miami offensive line.
After walking off the field, a South Florida Sun-Sentinel report says, Long sat on the medical cart while trainers focused on his knee. General manager Jeff Ireland was seen checking on the Pro Bowl tackle.
No further information was available.
[UPDATE: 5:25pm]: Long walked off the field and into the training facility under his own power. He was accompanied by Dolphins head trainer Kevin O'Neill. O'Neill returned to the field shortly after without Long.