In 1997, under the direction of Commissioner Bud Selig, Robinson's No. 42 was retired across all of Major League Baseball in an unprecedented tribute.
"I've always been very aware of Jackie Robinson," manager Bob Melvin said. "Not only is he one of the more impactful people ever in sports, but maybe ever in the country, period. He's opened a lot of doors. You'll hear people, especially baseball players, compliment and admire what he had to go through, and just a remarkable human being."
According to USA Today, four teams opened the season without a black player on their rosters: the Cardinals, Giants, Mariners and Rangers. Moreover, Major League Baseball says black players composed just 7.7 percent of Opening Day rosters and disabled lists. The A's have three African-American players -- Coco Crisp, Chris Young and Michael Taylor -- on their active roster, along with a pair of black coaches in Chili Davis and Tye Waller.
Such diversity extends to Oakland's front office, as well.
"We have all kinds here, and I think it's great, and I think the more diversified you are, the better off you are," Melvin said. "You learn that much more about people, and from our front office to the players, we feel like we're well represented amongst a lot of different types, and I for one am proud of the fact I'm part of that."
Jane Lee is a reporter for MLB.com. Read her blog, Major Lee-ague, and follow her on Twitter @JaneMLB. This story was not subject to the approval of Major League Baseball or its clubs.