Fans attending NBA games have relatively little to worry about. They don't generally have to be concerned with objects flying at their face like in baseball, and they aren't subject to Mother Nature as most attending NFL games are.

Aside from another Ron Artest-like event, NBA fans haven't had too much impinge on their live enjoyment of the game. Then came K.J. McDaniels.

McDaniels, who was selected by the Sixers in the second round of the 2014 NBA Draft, is quickly becoming a fan favorite in Philadelphia, due largely to his ability to block and alter shots as a perimeter player.

McDaniels leads all rookies with 1.57 blocks per game, and he is able to energize a crowd with the sheer ferocity of his blocks. This is good news for the Sixers, who were happy to secure someone so defensively dedicated in the second round. It may not be great news for those attending Sixers games however, as McDaniels' blocks apparently cause actual injury.

On one particular play in Toronto in November, McDaniels found himself as a weak-side help defender as Raptors' point guard Greivis Vasquez drove down the lane to the basket.

McDaniels came across the paint as Vasquez went up with the shot and volleyball-spiked it out of bounds. It looked cool, but apparently the block caused a concussion upon impact!

"I surprised myself," McDaniels told Sports Illustrated's Rob Mahoney of the block. "There was a lady who got hit by the ball who got a concussion, I believe," McDaniels said.

Ouch. Imagine that. You're just sitting there minding your business, catching some casual NBA basketball on a Sunday, and next thing you know you get the ball spiked at your head with such velocity that is causes a concussion.

Upon hearing of the result of his highlight-reel block, McDaniels sent flowers to the woman.

Still though, it may be a good idea to keep your head on a swivel if attending a Philadelphia 76ers game this season.