Jackie Robinson Day celebrated in space

Jackie Robinson Day was celebrated even in space this year.

While Rachel Robinson, the player's widow, and Commissioner Rob Manfred were set to honour Robinson in a ceremony at Dodger Stadium in conjunction with Major League Baseball's annual Civil Rights Game, astronaut Terry Virts wore a Dodgers jersey with Robinson's No. 42 along with a Brooklyn cap at the International Space Station orbiting Earth.

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Wednesday marked the 68th anniversary of Robinson breaking the major league colour barrier.

"I can remember reading a book about Jackie when I was in the first grade," Virts said in a video posted on MLB.com.

"Even at that young age, I was really impressed with what he did beyond baseball. What he did took courage, a lot of courage. He had to endure things that most of us could not imagine, and he had to do it while maintaining composure that most of us couldn't begin to muster."

Opening-day rosters included 8.3 per cent of players who identified as African-American, according to Richard Lapchick's Institute for Diversity and Ethics in Sport at the University of Central Florida. That was a slight increase from 8.2 last year, which equalled the study low set in 2007.

"There's a growing concern that our game does not reflect our society in the demographics. We'd like to think we could attract every good athlete from every walk of life," Red Sox manager John Farrell said.

Boston's David Ortiz posted his own tribute to Robinson on Twitter.

Robinson's No. 42 was retired throughout the major leagues in 1997. Commissioner Bud Selig decided in 2005 that all teams would honour Robinson each April 15.

Every major league player, manager and coach on the field wears No. 42 on the date including the Blue Jays.

Robinson was a six-time All-Star, the 1947 major league Rookie of the Year and the NL MVP in 1949, when he won the league's batting title.

"Martin Luther King came to my house one night for dinner 28 days before he died in Memphis," former teammate Don Newcombe said in Los Angeles. 

"He said to me: 'Don, I want you and Jackie and Roy Campanella and Larry Doby to know that without you, I would never have made it as successfully as I have in civil rights if it were not for what you men did on the baseball field.' I said:

'Martin, you're kidding.' He said: 'No, I'm not, and I want you to call Jackie tomorrow morning and tell him what I said."'