Newly signed with Oakland after seven seasons with the Yankees and one with the Angels, Matsui doubled for his 2,500th career hit (Japan and here combined). Athletics catcher Kurt Suzuki, who is fourth generation Japanese-American, then hit a fly ball to Ichiro, who caught the ball and threw out Matsui trying to tag up and advance to third. What are the chances of that happening anytime, let alone on Japanese Heritage Day? "I have no idea, but very slim, I guess," Oakland's Suzuki said, "Suzuki to Suzuki to Matsui -- out! That's pretty funny."
Matsui and Ichiro go back a ways. The two first met in high school. Matsui was a junior at Seiryo High School when its team traveled to play Aikoudai Meiden High School, where Ichiro was a senior. Teams frequently take communal baths in Japan, and because Matsui's school was the guest, it was allowed to use the bath first. But the first bath also is generally reserved for seniors, and when Ichiro arrived, he took note that Matsui was already in the water.
Skip ahead more than a decade, when Japan's two most famous players are both established in our major leagues. One winter they appeared together on a TV show in Japan, and Ichiro took advantage of the opportunity to ask Matsui a very important question: Why did you get in the bath first?
Matsui says Ichiro was joking when posing the question, but the fact he remembered the possible breach of bathing etiquette after so many years is pretty interesting.
Ichiro and Matsui are such icons that their fathers each operate private museums featuring their famous sons (the Ichiro museum has his orthodontic retainer from junior high; it's unknown whether the Matsui museum has his first copy of Playboy). The long-standing perception is that there also is a prickly rivalry between Matsui and Ichiro -- who are rarely seen speaking together. Matsui, however, disputed this when asked this week about the relationship between the two.
"We always greet each other when we see each other on the field, but we don't necessarily go out together away from the field or anything like that. But the relationship is fine," Matsui said through his interpreter. "Perhaps through the media and through the media and to the fans, maybe there is a rivalry that has been created. But me personally, I don't have any type of rivalry or feeling like that."
Ichiro declined an interview about his relationship with Matsui this week. When Matsui first joined the Yankees in 2003, Ichiro spoke very respectfully of him, but also told a reporter the two hadn't met despite the high school bath incident and despite the fact that the two played against each other in Japan's 1996 championship series, several Japan All-Star Games and in the 2002 major league tour of Japan. Robert Whiting, who has written books on Japanese baseball in general and Ichiro in specific, says he thinks Ichiro was initially jealous of the attention Matsui received because he was a home run hitter for the enormously popular Yomiuri Giants in Tokyo while Ichiro played for the Orix Blue Wave (kind of like the San Diego Padres of Japan) in Kobe. Ichiro complained once that he could hit .400 and Matsui still would get more attention.
"I think Ichiro felt superior to Matsui in every way as a ballplayer and resented the fact that Matsui monopolized the spotlight in Japan -- rated higher by fans, just because of his home runs and because he played for the Giants," Whiting wrote in an email. "Some of that spilled over in MLB, especially during Hideki's best years with the Yankees -- who had far more cachet in Japan than the Seattle Mariners did. I don't think there is any personal animosity, but their personalities are quite different."
That's an understatement. Ichiro is guarded and clearly dislikes dealing with the media. While he can be pleasant enough in a non-interview session, he often sits with his back to reporters during postgame questioning, dismissing the questions he doesn't like by saying they aren't good ones. Matsui is open, gregarious and accessible. Both, however, are well aware of the media's scrutiny -- even after the pair's combined 18 years in America, a half-dozen or more Japanese reporters are assigned to follow each on a daily basis.
"There's a big rivalry going on -- I think Hideki is winning," Oakland starter Gio Gonzalez joked of the media coverage.
Ichiro has had more personal success in America -- with an MVP, several batting titles, the single-season record for base hits, more than 2,200 hits in just 10 seasons, a career .330 average, 10 Gold Gloves and 10 All-Star Game appearances, he will eventually have a Hall of Fame plaque in Cooperstown even without counting his considerable achievements in Japan.
Matsui may not wind up in Cooperstown, but he has enjoyed a fair amount of success here, as well. He's played in two All-Star Games, driven in 100 runs four times, hit 25 or more home runs three times and has achieved an honor that has been frustratingly beyond Ichiro's reach (or even within his sight in recent years): the World Series MVP award in 2009.
While Ichiro appears stuck in another losing season (the Mariners enter the weekend 7-13 and last in the AL West), the Athletics are hoping Matsui can help them return to the postseason. The Athletics have one of the best rotations in the league, but they have lacked power and run production in recent years; Kevin Kouzmanoff led the team with 16 of Oakland's 109 home runs last season. The hope is that Matsui can help improve that. His best years are behind him, but he did hit 21 home runs with 84 RBIs last year and hit 28 home runs the previous season. He's batting .246 with two home runs and 11 RBIs this season.
"He's that intimidating force in the middle of the lineup we haven't had for years," Kurt Suzuki said. "He's done it for many, many, many years. To take those numbers he's put up and put him in the middle of the lineup -- it makes everyone around him better."
"It takes a lot of stress off the starting rotation and the bullpen," Gonzalez said. "We can go out there and now we'll have some runs to work with. It helps out extremely."
Ichiro turned 37 last fall but still is in great shape; he runs well enough to have stolen 42 bases last year and remains good enough defensively that he won his 10th Gold Glove last year. Matsui turns 37 this summer and has been reduced to a DH role. Matsui, who needs five more home runs to reach a combined 500 for his career, said he hasn't thought about whether he wants to end his career here or back in Japan.
As for the legacy the two will eventually leave behind, Matsui replied: "What Ichiro has achieved has been really incredible, to the point where I think he has become a role model for everyone to strive towards."
Both players donated generously to the Japan earthquake relief fund, about $1.2 million from Ichiro and $600,000 from Matsui.
"I don't know how things will pan out in the future, whether we'll work together in some fashion," Matsui said when asked whether he would like their relationship to grow. "But our feelings to make things better in baseball and be the bridge between America and Japanese baseball, that's a mutual feeling we have. I don't know if we'll work together, but I think he has that type of feeling toward baseball."
Jim Caple is a senior writer for ESPN.com.
Follow Jim Caple on Twitter: @jimcaple