On the subject of toughness, Zach Randolph struggles to find the right words. How do you describe being a bully on the low block and an unstoppable force on the boards and having an appetite for the bruising contact that comes with the job? "It's just in me," Randolph said. "I'm not backing down from nothing." Randolph's words will serve as the Grizzlies' mantra when the NBA playoffs begin this weekend. The league's second season is normally ruled by teams that defend at a high level and have a dominant post player. That's why the Griz are confident they will pose a difficult challenge for their first-round opponent. Sure, the Griz will have to deal with a higher seed with a certified superstar. But that team must tussle with Randolph, a 6-9 power forward who has transformed the Griz into a team that is dreaded for its toughness in the paint. "He works. He battles. He's not afraid to bump and grind," Griz coach Lionel Hollins said. "That takes a lot of toughness -- to be hit and to hit somebody. His aggressiveness in the post and on the glass makes our other guys aggressive." The attention paid to Randolph's relentlessness will become more pronounced in the playoffs. Opposing teams have spent most of this season crowding Randolph in the post and beating him up in an attempt to deny post position and catches. Randolph's response has been near flawless, as he has still managed to average 20 points and a career-high 12.4 rebounds. He has picked apart defenses by making smart reads and crisp passes out of double teams. And the veteran's improved mental toughness is what the Griz will count on in the postseason as much as his brute force. "The way Zach's played the past two weeks is the playoffs," Griz assistant coach Damon Stoudamire said. "He's seen a lot of double teams. He's found guys and been coy about his game. He involves everybody else, but he still gets his. Everybody knows if he doesn't play well we won't have a chance." Randolph said he's more comfortable leading by example, but his teammates will see a different side of him in the playoffs.