Rob Gronkowski: Low hits are part of the game

New England Patriots fans hold their breath every time a defender tackles Rob Gronkowski low.

Given the heart palpitations caused by such collisions, Pats fans got worked up this week when Broncos cornerback Chris Harris Jr. described hitting Gronk low, at the knees, as the best way to take down the 6-foot-6, 265-pound tight end.

Gronk issued a playful retort earlier in the week, but Thursday brushed aside any notion that he's worried about the Broncos targeting his knees.

"It's part of the game. I've been seeing it all year," Gronkowski said of low hits, via the team's official website. "I've been seeing it my whole career. I've just got to get low, get my shoulder down, protect the ball,…