Forty seconds of deafening silence. On the verge of winning his first NBA title, Doc Rivers was asked about his dad, the Chicago cop, and the engaging coach with an answer for everything could not address the loss of his best friend.

Grady Rivers died in November, early in the charmed season of his son’s bittersweet basketball life, and each day has been Father’s Day ever since. So when a reporter wanted to know how Grady had shaped Doc, the Celtics’ coach who can turn a season into a talk show offered his old man the greatest tribute of all:

Silence.

This was the news conference scene from the other day, with Rivers too emotional to speak in a roomful of people accustomed to hearing the friendly and frequent sound of his voice. His Celtics have a chance to defeat the Lakers for the championship on Father’s Day night, and win or lose, Rivers will be thinking about his dad’s sacrifices, just like tens of millions of American sons.

This is the redeeming value of sport, which needs good press these days wherever it can get it. Nothing bonds generations of men quite like the games they watch and play.

Rivers will be coaching for his father in Game 5, just like Tiger Woods will be trying to win his third U.S. Open title for a man he called “an amazing dad, coach, mentor, soldier, husband and friend.”

Earl Woods’ fingerprints are all over his son’s greatness. Earl famously told Sports Illustrated that his own flesh and blood “will do more than any other man in history to change the course of humanity. … He is the Chosen One. He will have the power to impact nations.”

However absurd the bluster, every father could relate to Earl Woods’ love and enthusiasm, and to his oversized desire for his child to have the world at his feet.

Just as every son can relate to the moving portrait Jim Nantz paints of his father in his book, “Always By My Side,” and to the scene of the elder Jim sitting in the booth and ignoring the Masters while silently watching his boy broadcast the event for hours.

The public stage was built by the devotion of fathers who toiled in anonymity to give their children a better day. But millions of productive private citizens, the 9-to-5 guys also were molded by men who taught them valuable life lessons through the forum of youth sports.

Fathers who poured so much of their time and energy into coaching teams, running leagues, preparing fields and rearranging schedules to accommodate parents, kids and umps. Fathers who contributed more hours to this cause than they did to their full-time jobs.

Those hours of blood, sweat and tears earn a working man no wage, no vacation time, no sick pay, but plenty of benefits. His time in the sun is rewarded by the unmitigated joy on his boy’s face when playing a boy’s game.

So all fathers and sons understand why Doc Rivers couldn’t speak the other day when asked about his old man. Grady Rivers was his Little League coach, and the friend and adviser who was there with a consoling word every time Rivers lost a playoff series to Michael Jordan or Larry Bird.

In Grady’s lifetime, Doc never won a championship ring as a player, and never won a playoff series as a coach. A trophy finally seized more than seven months after Grady’s death will feel a little heavier in Doc’s hands.