On April 15, every player in baseball wore the number 42 to celebrate a man who changed the game forever

Let’s take a step way back to 1883. Cap Anson, a Hall of Fame first baseman for the Chicago White Stockings (now the Chicago Cubs), declared his team would not play the minor league Toledo Blue Stockings. This was because Toledo had Moses Fleetwood Walker, the only black man playing in the minors at the time.

Although the White Stockings eventually competed, the next year, Anson sent a threat to the  league that forced Walker to sit. This moment led to the “baseball color line.” The game was considered a white-men-only sport for many years. Yet, there was no written rule or law that made this official; it was just an unspoken reality.

That “gentlemen’s agreement,” however, was thrown away in 1946. Branch Rickey, general manager for the Brooklyn Dodgers at the time, was looking for some young stars that would ultimately enhance his team’s roster. His eyes were set on an immensely talented second baseman and former UCLA multi-sport star. There was only one problem—he was black.

This man was Jackie Robinson. Growing up in Pasadena, California, Robinson was born into a family of tenant farmers. His older brother introduced him to the idea of pursuing sports due to his evident talent. He was the star on his baseball, football, basketball and track teams in high school. He attended Pasadena Junior College for a few years and then found himself at UCLA as a scholar-athlete.

After a brief time with the Army, Robinson became a competitor in the Negro Leagues, which were introduced and developed by the neglected black baseball players in the late 1800s and early 1900s. However, Robinson was unimpressed by his team, the Kansas City Monarchs. The players were not focused on the game, and many were heavy gamblers. But Robinson played well with the team, well enough to be noticed by Rickey in 1946.

His talent and composure impressed Rickey, and after a time of extensive interviews and contemplation, Robinson was invited to join the Montreal Royals, the top farm club for the Dodgers at the time. He played excellent baseball for the Royals and was given the opportunity to play for the Dodgers in the 1947 season.

Robinson’s rookie campaign was incredible. He played in 151 games, with a batting average of .297 and an on-base percentage of .383, scored 125 runs, drove in 48 runs and led the league with 29 stolen bases. He won the Major League Baseball Rookie of the Year Award, which is now recognized as the Jackie Robinson Award.

Robinson played his entire nine-year career with the Dodgers. He finished with a career batting average of .311, won the NL MVP in 1949, was named an All-Star six times and competed in six World Series, winning his lone ring in 1955. Robinson’s accomplishments on the field are clearly superb, but his play is not what made him so influential, rather it was Robinson’s approach towards changing the environment of baseball and American society.

Rickey was aware that Robinson would be forced to face racism and death threats from opposing teams, fans and even his own teammates. One of the reasons the general manager was so high on Robinson was because of his promise towards keeping a steady head. Robinson was forced to endure a multitude of unfair criticisms throughout his rookie year. Despite a slow start to his first professional season, his athleticism took hold, and he let his play do the talking for him.

Robinson’s level of professionalism was inspiring not only to black players, but several organizations and general managers as well. His success led to an uprise in black athletes and other minority players being signed by MLB teams. Men such as Roy Campanella, Larry Doby and Don Newcombe were all minority players who were named All-Stars in the late 40s and early 50s.

Robinson’s play and attitude began a movement in America that saw people of African decent stand up for their rights as free individuals. Martin Luther King Jr., one of the most celebrated civil rights activists in history, was inspired by Robinson’s peaceful mindset and ultimately mimicked his approach in his movement. King also stated that if it wasn’t for the culture shift in baseball, it wouldn’t have opened the eyes and hearts of a majority of activists from the 50s and 60s.

Today, the game of baseball has become a beautifully diverse sport. In 1947, 98.3 percent of players were white. By 2016, that number decreased to 63.7 percent with demographics such as African-American, Latino, Asian and others comprising the remaining 36.3 percent. In addition, baseball has become quite prevalent in other countries like Mexico, Puerto Rico, the Dominican Republic and Japan.

So, when players wear the retired number 42 on their jersey every year on April 15, it is more than just representing a baseball player. It is to acknowledge the beauty of diversity amongst the league. It is to support the players and individuals that engage with the sport all around the world. It is to reminisce on the hardships and accomplishments that black players endured in their battle of equality. It is possible that none of these things could have been done without Robinson, and because of that, we must thank you, Jackie.