OKLAHOMA CITY (AP) -- Memphis forward Zach Randolph usually imposes his will on opponents with his strong, aggressive play.
Randolph, a 6-foot-9, 260-pound forward, averaged 17.4 points and 10.1 rebounds during the regular season. In the playoffs, he's up to 18.3 points per game, but he has made just 36 percent of his shots. The Thunder say Perkins' strength and Ibaka's athletic ability have been a tough combination for Randolph to handle. The two have switched off on him and mostly defended him straight up, sometimes even switching during a play.
''They're doing an amazing job,'' Thunder guard Russell Westbrook said. ''I don't think they're getting the credit they deserve. I think a lot of the attention is on Kevin (Durant) and myself, but I think they're doing a great job of defending those bigs, which is tough to do.''
In Game 4 on Saturday night, Randolph made 5 of 14 field goals and 1 of 5 free throws. The Thunder won in overtime to tie the series at two wins apiece, and they will try to keep their success going in Game 5 Tuesday in Oklahoma City.
In Game 1, Randolph made just 7 of 21 shots. He was back to normal in Game 2, making 10 of 20 shots and scoring 25 points. He bottomed out in Games 3 and 4. In Game 3, he made just 5 of 20 shots, but the Grizzlies managed to win in overtime. Things weren't much better in Game 4.
It's not just Randolph's shooting that is suffering. His rebound average is down to 8.5 per game, and he has made just 19 of 30 free throws in the series. He will not change his approach.
''Just keep on being me, keep playing,'' he said.
The Grizzlies are working to figure out ways to get Randolph open, but it is difficult to come up with new things against a team that knows him so well. This is the third time in four years the teams have met in the playoffs.
''We've got to try to get some motion with the ball movement from side to side, so when the ball does come back to him, he gets the ball at a better position closer to the basket,'' Grizzlies guard Mike Conley said. ''I think he's been too far out having to work too hard to get to his spot.''
With Ibaka, the Thunder have one of the league's most athletic interior defenders. The 6-10 forward was fourth in the Defensive Player of the Year balloting after finishing third in 2013 and second in 2012. Ibaka has at least four blocks in three of the four games.
In Perkins, the Thunder have a 6-10, 270-pound brick wall with veteran savvy who won't give Randolph an inch.
''Perk is one of the premier defenders in the league,'' Thunder coach Scott Brooks said. ''He does that game in, game out. He gives everything he has to stop his man from getting good post position. That's his first line of defense.''
Memphis coach Dave Joerger acknowledged that Perkins is keeping Randolph out of his comfort zone, and that the Grizzlies will need to do little things better to get him going.
''Ball movement is always good, where other guys are a threat,'' Joerger said. ''And then he (Randolph) gets duck-ins or advance passes and post-ups from there.''
Brooks said he expects Randolph to be his usual assertive self in Game 5.
''Zach is not going to give up,'' Brooks said. ''That guy is as good as any player in this league at playing aggressive low-post basketball. He's relentless in his pursuit of the basket, and when the offensive boards are available, he's always crashing. You always have to stay between him and the basket.''