Baltimore Ravens coach John Harbaugh didn't express any concern about the condition of footballs used in his team's Jan. 10 playoff loss at New England.

The Patriots are under investigation for using game balls that were inflated significantly below the NFL's requirements in the AFC Championship Game, which was played a week after the Ravens' game at Gillette Stadium. The NFL has found that 11 of Patriots' 12 game balls were underinflated, league sources told ESPN.

"We did not notice anything," Harbaugh said Wednesday. "We never had a ball that they used or anything like that on offense, so we don’t know anything about that in our game. We didn’t have a chance to handle any of their offensive footballs."

Harbaugh, who is in Arizona preparing to coach in the Pro Bowl, said the issue of the Patriots' footballs is "not really something that is in the forefront of our mind." Some people in the Ravens organization were questioned by the NFL during the league's investigation, but Harbaugh said he didn't know the details of the conversations.

On Tuesday night, CBS Sports reported that some Ravens believed kicking balls used in New England were slightly under-inflated. Harbaugh said there was a reasonable explanation for it.

"As far as the kicking balls, it was 20 degrees out, so the balls were softer," Harbaugh said. "Our guys told us during the game, and I just chalked that up to the fact that it was cold and that both teams were kicking the same kicking balls, so I didn’t think really anything of it during the game. Other than that, it’s not something we’ve really given any thought to at all."