OKC Thunder's Kendrick Perkins says tussle with Dallas' Dirk Nowitzki 'just playoff basketball'

Veteran point guard Derek Fisher, who is stationed in a stall next to Perkins, was asked what he thought of the altercation.

"I don't know if I'd call it an altercation," Fisher said. "These two teams have played just about more than anybody in the league in the last two years. There isn't much space on the floor to operate, so offensively and defensively, guys are going to be pumping and pushing and getting after it."

The Thunder and Mavs indeed have met frequently the past two seasons with eight regular-season games; two preseason games this season; and seven playoff games with two more to come by Saturday.

For OKC, this is the second straight playoff series against Dallas.

"Each side knows each other's personnel and scouting reports," Perkins said. "They probably know all our plays, we know all their plays, so it's really like will-power. A lot of it is just mental toughness and heart and who's going to go get it."