Braves super-prospect Ronald Acuña Jr. beat out an infield single in the top of the 7th inning against the Red Sox Sunday. Shortly after crossing first base, while signaling to the umpire, Acuña took a bad step with his left leg and something very ugly and unnatural happened in the area of his knee:

To the surprise of, well, anyone who saw the injury live or watched the video, Acuña was able to limp off the field more-or-less carrying his own weight.

He was replaced in the lineup by Preston Tucker. It will be an absolute miracle if he avoided any major injuries in that fall. Yikes.