"This is a wonderful gesture on Ken's part and a fitting tribute to the great Jackie Robinson and one, I believe, that all clubs will eagerly endorse," Selig said in a statement. "To make this happen, I gladly will temporarily suspend the official retirement of uniform No. 42 on that day."
Ten years ago, Selig announced that all clubs would retire Robinson's number. But for one game only, he will allow players on every club the rare opportunity to wear it again.
"That would be a neat thing to do," said Mariners reliever Arthur Rhodes, one of two African-Americans on the Mariners roster. "I'd love to wear Jackie's jersey for one game. It would be a nice feeling to have Jackie Robinson's number on my back.
"He was a hard player. I play hard every day. He went out and did his job. I'd do it, go out there and represent Jackie Robinson."
The team's other black player, outfielder Jason Ellison, also said he'd love the opportunity.
"He set the groundwork for us, obviously," Ellison said. "He put up with a lot of stuff. He stuck it out and laid it out for the rest of us.
"It would be great, outstanding."
There are 15 games scheduled on April 15. The celebration's focal point will be at Dodger Stadium. It will be broadcast on ESPN and will feature Rachel Robinson, Jackie's wife and founder of The Jackie Robinson Foundation, their daughter, author Sharon Robinson, and several of Jackie's former teammates.
Manager Mike Hargrove would like to find opportunities for his bench players to start or play more, but it has been hard thus far.
"The American League is not easy on extra players," Hargrove said. "It's not a game where with the DH in there you're going to pinch-hit a lot," he said. "Bench players don't get used a whole lot, so they have to do a lot of extra work to keep themselves sharp.
"You try to slot them in here and there to keep them afloat at the plate, but sometimes we're not able to do that. Regulars are regulars for a reason. We're not playing Little League baseball, where everybody gets to play three innings every game. They have a job to do and they have to do it."
The three prominent bench players -- Ben Broussard, Jamie Burke and Willie Bloomquist -- all had outstanding springs. They hit a combined .346 with three home runs and 16 RBIs.
Reliever Brandon Morrow's Major League debut, which teetered early on disaster, was one of the feel-good stories that came out of Tuesday's 8-4 victory. Morrow allowed the first two batters to reach on a four-pitch walk followed by a single.
The 22-year-old right-hander then settled down and retired the next three hitters without allowing a run.
Hargrove said staying under control "was probably the most impressive thing." He added that Morrow's quiet confidence sets him apart from other players his age.
"He's a self-possessed kid and stays and under control," Hargrove said. "I'm sure he was nervous and jittery, but he didn't show it. That's good to see, because you don't want the other side to see that because that gives them the edge."
Morrow became just the second player from the 2006 First-Year Player Draft to appear in a big-league game. Andrew Miller had a clause in his contract for a September callup with Detroit last season, but this year he's playing for Class A Lakeland.
Reliever Julio Mateo notched his fifth consecutive win Tuesday. He has not been the losing pitcher since July 18, 2006, a stretch of 18 appearances. ... Dave Niehaus, who broadcast his 4,600th Mariners game Tuesday, now has done 4,601 of the team's 4,678 games.
The Mariners are off Thursday, but on Friday in Cleveland at 1:05 p.m. PT, left-hander Horacio Ramirez makes his Mariners debut. Ramirez was acquired in an offseason trade from Atlanta for reliever Rafael Soriano.