MIAMI — Not everybody in Dallas rejoiced when Mavericks forward Dirk Nowitzki spun past the Miami Heat’s Chris Bosh for
the winning layup Thursday night in the waning seconds of Game 2 of the N.B.A. finals.


In high school, Bosh was a star who helped lead Lincoln of Dallas to the 2002 Class 4A championship.

It was a rare lapse for Bosh, whose play in this postseason, especially on defense, has been stellar. Entering that game, he was averaging 18.6 points and 8.9 rebounds in the postseason and giving lie to the widely held belief that the Heat triumvirate of Dwyane Wade, LeBron James and Bosh is two and a half megastars. “Just watching him grow up as a player in this playoff series has been awesome,” Wade said of Bosh after the Heat’s Game 1 victory. For those who remember Bosh as the best player on one of the greatest high school basketball teams in Texas history, Nowitzki’s final drive to the basket was hard to watch. Leonard Bishop, who coached Bosh at Lincoln High School in Dallas, immediately harked back to the last time
Bosh stumbled on a big stage, at the 2001 Class 4A state championships, when he fouled out in a 2-point semifinal loss to San Antonio Lanier. He came back the next year to lead the Tigers to an undefeated season and the 2002 Class 4A state championship. That team was also the first from Texas to finish a season ranked No. 1 by USA Today. “Chris always set high standards, and he was a perfectionist,” Bishop said in a telephone interview. “He never stopped working to get better.”
The 2002 Lincoln squad was not unlike this season’s Heat team: tenacious on defense, supremely athletic and unusually close-knit. When Bishop watches Bosh rebound and kick the ball out to Wade or James, or expend most of his energy on defense, he sees the teenager who cared more about winning than individual statistics. Bosh, in turn, looks at the chemistry the Heat developed as the season wore on, and thinks back to his senior year of high school and the team
that finished 40-0. “As far as camaraderie, working together and having fun on and off the court, this has been the first time I’ve experienced anything like it,” he said. Bosh did not fully appreciate how special that undefeated team was until
he spent a year at Georgia Tech and seven more with the Toronto Raptors, starring on squads that did not coalesce or contend. The desire to recapture the rapture of a championship season drove him to sign as a free agent last summer with the Heat. Call it karma or a quirky coincidence, but Bosh’s road to another title has circled back to the city where his journey began. The Heat’s appearance in the N.B.A.finals against the Mavericks has divided the loyalties of Bosh’s former
teammates. Do they root for their hometown team, or their homeboy? Bishop’s son, Leonard, who was a year behind Bosh on the Lincoln team, picked the Heat to win in a dinner bet with Kevis Shipman, a starting guard on the 2002 championship team and a longtime Mavericks fan. Shipman has a photograph of Nowitzki and Jason Terry, the holdovers from
the 2006 Mavericks team that advanced to the N.B.A. finals, displayed on his Facebook page. He sounded ambivalent about winning the bet. “I’m a die-hard Mavs fan, but I really want Chris to do well,” ” he said by telephone. With the best-of-seven series even at 1-1 and shifting to Dallas for Games 3, 4 and 5, the focus figures to switch from Wade and James to Bosh. When asked last week about playing his hometown team in the finals, Bosh momentarily dropped his businesslike mask. His eyebrows arched, his eyes widened and for a fleeting second he looked like a comic about to
deliver a punch line. Just as quickly, his poker face returned. “It brings some elements to it that normally wouldn’t be there,” Bosh said, “so I have to do a good job to focus and play basketball. I’m keeping that in mind.” Bosh showed that dual personality in high school. He would be recording a silly video one minute, then studying for an exam the next. “Chris is still the same goofy guy that wants to laugh and joke,” the younger Bishop said. “But he also has a serious side. That’s the good thing about Chris. He has a switch that he can turn on and off.” On the basketball court, Bosh is all business. He arrived at Lincoln as a 6-foot-7 freshman with less meat on his bones than a chicken wing. Shipman, his classmate, said: “A lot of people talked about how he was too skinny to be a good post player. He didn’t listen to their talk, but
it made him work harder.”