For Derek Fisher and Lakers, Role Reversal LOS ANGELES - The curtain dropped, dramatic music thumped, and a blur of highlights played across the tapestry hanging over the Staples Center court. Then, three words: "Time marches on." As if the Los Angeles Lakers needed any reminders. At the time of that stirring introduction Friday night, the Lakers were staring at a 2-0 deficit in the Western Conference semifinals. The Oklahoma City Thunder looked younger, springier and hungrier. Time had dulled the Lakers" luster and withered their championship core. And one of their most important figures of the last decade was on the opposite bench, wearing a powder-blue No. 37 jersey. Derek Fisher - veteran of five Laker championships, author of countless clutch shots, confidant to Kobe Bryant - was making his Staples playoff debut as an opponent. "It's just very strange," Bryant would say later, after leading the Lakers to a gritty 99-96 victory. I'm used to having him in the locker room. I'm used to hearing his voice, saying things that he and I have talked about, in terms of the direction of the team and what the team needs to hear, and then he vocalizes it. And I don't have that. Does he miss Fisher? This has been a difficult, transitional season for the Lakers, and particularly for Bryant, who has bidden farewell to one trusted voice after another: Coach Phil Jackson last summer, Lamar Odom in December and Fisher - perhaps his closest friend in the league - in February. Bryant and Fisher had been teammates for most of their 16 years in the N.B.A. and had navigated nearly every challenge. "We've been down, 3-2, in the N.B.A. finals," Bryant said. We've been down, 3-2, in the Western Conference finals. We've been down, 2-0, to San Antonio. So you miss that, you miss that. Three months ago, in a continuing campaign to refresh the roster, the Lakers sent Fisher to Houston, to make room for Ramon Sessions, a younger, quicker guard who was acquired in a separate trade. Fisher arranged a buyout with the Rockets, then quickly signed with the Thunder, a dynamic young team with championship aspirations and a need for veteran guidance. It is the perfect fit for Fisher, who says he is "extremely happy with the way this has turned out." The Thunder were preseason favorites to make the finals and finished with the second-best record in the Western Conference. After losing to Dallas in the conference finals a year ago, they seem ready to take that next step. Fisher knows what it takes. He rode shotgun with Bryant through five Laker championship runs from 2000 to 2010, while growing into one of the most respected players in the league. In Los Angeles, Fisher served as a calming influence in a locker room racked by tensions between Bryant and Shaquille O'Neal. In Oklahoma City, he is more a mentor than a marriage counselor. At 37, Fisher is the oldest player in the locker room - 14 years older than the Thunder's two superstars, Kevin Durant and Russell Westbrook. Durant was 11 when Fisher won his first N.B.A. title. "Leadership," James Harden, a 22-year-old Thunder guard, said of Fisher. He says stuff every single day that helps us out and motivates us to want to go out there and compete. The Lakers had no doubt about Fisher's makeup. It was his quickness and his jump shot that worried them when they decided to replace him with the 26-year-old Sessions. Fisher was averaging just 5.9 points - his lowest mark in 13 years - and had a .383 shooting percentage at the time of the trade. "Nobody can dispute who Derek is and what he's done for this franchise," Mitch Kupchak, the Lakers" general manager, said. But we felt we had to look forward a little bit. The logic of the deal was not lost on Fisher, but he was upset that team officials never informed him directly, leaving him to find out the news on his own. It was a distasteful way to leave a franchise to which he had given so much. But then, this has been a tumultuous season on many fronts. As the president of the players union, Fisher worked tirelessly last summer and fall to negotiate a new labor deal and end the lockout. Then came the trade. More recently, Fisher has been at odds with the union's executive director, Billy Hunter, over the union's business operations. Last month, the union's executive committee voted unanimously to ask Fisher to resign. He has refused. Fisher declined to talk about the issue, but Bryant spoke passionately in his defense. "He's such a good guy - it's tough when people try to take advantage of his kindness," Bryant said. He's been the consummate professional his entire career, so he's not going to respond or do anything out of character. This has always been the way for Bryant and Fisher, supporting each other with a timely pass or a timely call. Now each stands in the other's way of a sixth title, quite literally - Fisher guarded Bryant on two consecutive possessions in the fourth quarter of Game 3. Bryant promptly hit two shots over him. Fisher's replacements have mostly struggled to replicate his stout defense and his timely 3-point shooting. When Steve Blake of the Lakers missed a 3-point shot at the final buzzer of Game 2, it was hard not to think, "Fisher makes that." "You can't replace Derek Fisher," Kupchak said. But time marches on.