From: http://seattlepi.nwsource.com/baseball/18800_aguy16.shtml
Q: Why is Ichiro Suzuki allowed to have only Ichiro, his first name, on the back of his jersey? Won't that set a dangerous precedent?
AG: Less dangerous than sitting in the stands when Chuck Knoblauch is playing second. And not a precedent either -- pitcher Vida Blue used to have Vida on his jersey, and Chili Davis had Chili (the nickname, not the food). Regarding Ichiro, the Mariners informed the league that he had worn only Ichiro on his jersey during the past nine years in Japan and planned to continue that practice. No problem ensued.