That loud cracking sound you hear is the last major taboo in sports being demolished today. All-American defensive lineman Michael Sam, a prospective NFL draft pick from Missouri, became the first player entering pro football to declare that he is gay. He is a major talent -- SEC defensive player of the year -- and the waves of change will ripple through all sports. Retired athletes have declared their sexual orientation, but this is an active athlete. The preliminary reaction of NFL personnel that this revelation will drop Michael Sam in draft status is the last gasp of unreasoning prejudice.

This barrier has been ready to fall for several years now. NFL players will accept him, with rare exceptions, and like a Jackie Robinson in baseball, this announcement will pave the way for many more to come. Why will he be accepted?

First, athletes are part of a younger much less judgmental generation than older people in this country. That age group has different attitudes about everything from gay marriage to marijuana. They have a much more libertarian "live and let live" philosophy. Even the evangelical Christian groups among young athletes may not believe the Bible condones such behavior, but do not take it out on individual gays.

Football has been merit based for some time. Players of different races and religions bond together to achieve a united front. They bleed together and watch each other’s backs. Their key question is -- is their teammate willing to pay the price in training, practice and the games to bring them victory. In Sam, they have a rugged, tough team leader with a proven track record. He figures to be a mid-to-lower round draft pick, but the salary cap limitations dictate that a larger number of lower paid rookies need to make the roster and produce. His team will have two questions -- can he rush the passer, can he stuff the run?

I grew up in the 50s when there were no blacks or women in broadcast or reporting roles. Today it is hard to remember that time ever existed. Civil rights and equal rights legislation and changing attitudes have broken theoretical barriers in all professions. Sports are more than ready for this change.

Being gay as an adolescent in team sports is often a terrifying status. Teenage boys who are defining their own sexuality use crude and cruel language and stories in the locker room stereotyping gays. We have no idea how many actual gays exist today in sports because they are so tightly closeted. Many will feel more free to live honestly.

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Back in the 70s and 80s, the society was far from ready. I would have counseled a gay athlete that he would have better acceptance declaring he was a communist than being gay. When the president of the United States declares he is supportive of gay marriage -- the time for honesty and acceptance has clearly come.

Michael Sam appears tough enough to weather any blowback. He grew up in tough circumstances in a small Texas town. He saw his oldest brother killed, lost a baby sister, had another brother permanently disappear, and has had two brothers in prison. In his first television interviews he was articulate, bright and seemed at peace with himself.

This day marks a signal change in acceptance of gays in sports. One day, kids will not believe this was ever an issue. It is a triumph for decency and tolerance.

-- Leigh Steinberg has represented many of the most successful athletes and coaches in football, basketball, baseball, hockey, boxing and golf, including the first overall pick in the NFL draft an unprecedented eight times, among more than 60 first-round selections. His clients have included Hall of Fame quarterbacks Steve Young, Troy Aikman and Warren Moon, and he served as the inspiration for the movie "Jerry Maguire." Follow him on Twitter @leighsteinberg.

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