CHICAGO -- With the rate of African-American players at its lowest level in two decades, Reds manager Dusty Baker was a little surprised that Major League Baseball received its highest grade ever for racial diversity in hiring.

MLB received an A-minus for the first time on Tuesday from Richard Lapchick, director of the University of Central Florida's Institute for Diversity and Ethics in Sports. But just 8.2 percent of the league's rosters had black players last season, compared to 8.4 in 2006.

"That grade should be down then," Baker said Tuesday, which was Jackie Robinson Day in Major League Baseball.

Baker is one of eight minority managers working in MLB this season. He has not been able to notice improved efforts to hire minorities in baseball's front offices.

"It's hard for me to say," Baker said. "All I can see is what's on the field between managers, coaches and players -- field personnel. I don't know who is in everyone's office."

Although baseball has worked over the past decade to improve its presence in urban areas and inner cities, Baker concedes that conditions are tougher than ever for the current generation to play the game.

"I think economics is a big part of it," Baker said. "It's expensive to play baseball. It's a very affluent sport now with select teams, travel teams, equipment. It's going to cost you between $500 to a couple of thousand dollars for a kid to play with insurance, uniforms, all kind of stuff."

Baker and right fielder Ken Griffey Jr. wore the temporarily un-retired No. 42 Tuesday on the 61st anniversary of Robinson's breaking of baseball's color barrier.

Inside his office, Baker had two No. 42 jerseys hanging from his door. One of them will be auctioned to raise money for the Jackie Robinson Foundation and he's keeping the other.

"I'll put it in the trophy case next to my throwback Jackie Robinson 42 jersey that they gave out a few years ago," Baker said. "I got a Jackie Robinson wall in my house in my workout room. I have photos of Jackie and Pee Wee [Reese], and another great color photo of Jackie, Carl Furillo, [Don] Newcombe, [Roy] Campanella, Pee Wee, [Duke] Snider, the whole starting lineup. That was an awesome photo."