Across multiple eras, these icons made permanent and lasting marks in each of their respective fields. We hold their performances as a standard to measure the successes of others who try and achieve their levels of greatness.

Muhammad Ali

"Don’t count the days; make the days count."

He called himself 'The Greatest,' and to many he was not only the greatest boxer, but the greatest sportsman who ever lived. A man who burst into the national consciousness in the early 1960s, when as a young heavyweight champion he converted to Islam and refused to serve in the Vietnam War, and became an emblem of strength, eloquence, conscience and courage. Ali was an anti-establishment showman who transcended borders and barriers, race and religion. His fights against other men became spectacles, but he embodied much greater battles too.

“If you even dream of beating me you'd better wake up and apologize.”

Deion “Prime Time” Sanders

“If your dream ain't bigger than you, there's a problem with your dream.”

After Deion Sanders, one of the most electrifying athletes to ever play sports, was drafted by the Falcons in the 1989 NFL draft, he also signed on to play baseball with the New York Yankees. Playing for both teams, he became the only athlete ever to hit a home run and get a touchdown in the same seven-day period. He is also the only athlete to ever compete in the World Series and a Super Bowl.

“They don't pay nobody to be humble. Some people will come out to see me do well. Some people will come out to see me get run over. But love me or hate me, they're going to come out.”

Jackie Robinson

"There's not an American in this country free until every one of us is free."

Jackie Robinson was an American professional baseball player who became the first African American to play in Major League Baseball in the modern era. Robinson broke the baseball color line when he started at first base for the Brooklyn Dodgers on April 15, 1947.

"Life is not a spectator sport. If you're going to spend your whole life in the grandstand just watching what goes on, in my opinion you're wasting your life."

Kareem Abdul-Jabbar

“I think that the good and the great are only separated by the willingness to sacrifice.”

When Kareem Abdul-Jabbar left the game in 1989 at age 42, no NBA player had ever scored more points, blocked more shots, won more Most Valuable Player Awards, played in more All-Star Games or logged more seasons.

His list of personal and team accomplishments is perhaps the most awesome in league history: Rookie of the Year, member of six NBA championship teams, six-time NBA MVP, two-time NBA Finals MVP, 19-time All-Star, two-time scoring champion, and a member of the NBA 35th and 50th Anniversary All-Time Teams. He also owned eight playoff records and seven All-Star records. No player achieved as much individual and team success as did Abdul-Jabbar.

Players 10 years his junior couldn’t keep up with Abdul-Jabbar, whose strict physical-fitness regimen was years ahead of its time in the NBA.

But if others have since emulated his fitness regimen, no player has ever duplicated his trademark “sky-hook.” Although labeled “unsexy” by Abdul-Jabbar himself, the shot became one of the most effective weapons in all of sports. An all-around player, Abdul-Jabbar brought grace, agility, and versatility to the center position, which had previously been characterized solely by power and size.

Despite his incredible success on the court, it wasn’t until the twilight of his career that Abdul-Jabbar finally won the universal affection of basketball fans. He was a private man who avoided the press and at times seemed aloof. “I’m the baddest among the bad guys,” he once told The Sporting News.

But late in his playing days Abdul-Jabbar began to open up, and as his career wound to a close, fans, players and coaches alike expressed their admiration for what he had accomplished in basketball. During the 1988-89 season, his last, Abdul-Jabbar was honored in every arena in the league.

“You can't win unless you learn how to lose.”

Shawn “Reign Man” Kemp

“I don't just want to be the best player in the NBA, I want to be the highest paid.”

When Shawn Kemp was drafted by the Seattle Supersonics in 1989, he became the fifth player to go directly to the NBA from high school. His exceptional talent and fierce presence on the court drew comparisons to Michael Jordan, but Kemp's youth was seen as a serious obstacle to his ever reaching superstar status. In a few years the young forward proved that he was indeed All-Star material. His screaming slam dunks and dramatic blocks were loved by fans.

“Anytime you struggle, people are always going to say something.”