Washington Redskins quarterback Robert Griffin III admitted he was shocked when his dad showed up in the locker room after the 27-6 defeat to the San Francisco 49ers.
But Griffin III defended Griffin II's right to be there, and hit out at those who questioned his presence in the wake of the heavy home defeat.
"He showed up, I was shocked that he was there, but he meant no harm," Griffin III told ESPN.
"Anybody out there that's going after my dad needs to back up. That is my father. I will protect my family and he served 21 years in the military.
"I know that's not an excuse for anything that he does, but he's not overstepping his bounds. So I hope that people will respect that and back off."
When asked what his dad was doing there, Griffin III said: "He asked me if I was OK and I said, 'Yeah, I'm all right'. And me and him just talked and that's it."
Griffin came under fire from an aggressive 49ers defense on Monday night, and the second-year quarterback was sacked four times.
The Redskins (3-8) have endured a nightmare season, with Griffin failing to match the heights of his fantastic rookie year.
He threw for just 118 yards against the 49ers, with no touchdowns and one interception as San Francisco's defense had little trouble in breaching the Redskins' offensive line.
One play in particular saw Griffin caught by a nasty kick to the private parts - unintentionally - and the Redskins gunslinger said his dad was just doing his parental duties when he came to check up on his son after the game.
"I don't what all has been said, I just know it hasn't all been positive," Griffin said. "He wanted to do his fatherly duties and step in there to see if I was OK." Griffin said he was kicked in his private parts.
"No mom wants to see their kid out there getting hit at all," Griffin said. "So like I said, it was just him being a father, my mom being a mother and there's no problem in that."