If the San Antonio Spurs beat the Miami Heat and win 2014 NBA title, there will be a 15-year gap between Tim Duncan's first NBA title and his fifth NBA title.

At age 38, Duncan has long since cemented his status as one of the best players of all time. Of all the accolades he has amassed through his career, his longevity is perhaps the most impressive part of his résumé.

Duncan won his first championship in 1999.

When he was hoisting the trophy, the three stars of the Miami Heat were still teenagers who only dreamed of playing in the NBA.

Here's what they looked like:

LeBron James was a 14-year-old going into his freshman year in high school:

Dwyane Wade was a 17-year-old junior in high school. He was just 5'8" tall before a growth spurt going into his junior season:

In 1998, when Duncan started his title-winning season, 14-year-old Chris Bosh was still shorter than his dad:

Bosh, who grew up in Texas, said last year that he had Duncan posters hanging in his bedroom during that 1999 run.

Duncan has been a NBA role model for longer than these Heat stars have been adults. He's one of the best players ever, and what he's doing in his late-30s can only be matched by Kareem and a handful of other legends.