MLB teamIf not for the early arrival of his son and the temperamental back of his teammate, Daisuke Matsuzaka would likely have been just a spectator for his first game in his native country as a member of the MLB team Boston Red Sox. Or, he might not have been there at all.

Instead, he'll take the mound against the MLB team Oakland Athletics at the Tokyo Dome on Tuesday, when the Red Sox begin defense of their World Series title as Major League Baseball opens its regular season in Japan for the third time.
The 27-year-old Matsuzaka pitched eight seasons in Japan with the Seibu Lions, making his professional debut at the Tokyo Dome in 1999 in a win over the Nippon Ham Fighters. When he became available through the posting system before last season, the MLB team Red Sox submitted a winning bid of $51.1 million to negotiate with the star right-hander.  
After signing a six-year, $52 million deal to pitch for MLB team Boston, the Tokyo native went 15-12 with a 4.40 ERA and 201 strikeouts in 2007. He helped the MLB team Red Sox to their first AL East title since 1995 even though he sometimes struggled with his command while adapting to a new league and country.  
Matsuzaka, who started and won Game 7 of the ALCS against MLB team Cleveland and Game 3 of the World Series against Colorado, lost his only start against Oakland last season, allowing just two runs in seven innings of a 2-0 defeat June 5.  
Red Sox ace Josh Beckett was originally slated to pitch Tuesday's opener, with Matsuzaka to follow in the second game Wednesday, but Beckett remained in the United States due to back spasms. Right-hander Curt Schilling is also out until at least the All-Star break with a shoulder injury.
There was doubt about whether Matsuzaka would also skip the series to be with his pregnant wife in Boston, but the couple's son was born March 15.  
The MLB team fans at the Tokyo Dome gave a warm reception to MLB team Boston's other Japanese player at an exhibition game over the weekend, as Hideki Okajima is also making his first return after pitching 10 seasons in his native country.
 Okajima came to the MLB team Red Sox in 2007 with minimal expectations compared with Matsuzaka, but ended up serving as one of Boston's most reliable relievers, finishing the season with a 2.22 ERA.
The MLB team Red Sox return a similar roster to the one that won them their seventh championship last season, as they re-signed World Series MVP Lowell after he had a career-high 120 RBIs in 2007. Rookie Jacoby Ellsbury, who took the center field job from Coco Crisp during the playoffs last season and hit .438 during the World Series, is expected to be the starter.
Boston's lineup should once again be one of the best in the AL, with David Ortiz (.332 average, 35 home runs, 117 RBIs, 116 runs), Manny Ramirez (.296, 20 HRs, 88 RBIs) and Lowell anchoring the offense.  
Oakland's arrival in Japan has come with considerably less fanfare, especially after the MLB team A's suffered through their first losing season since 1998 last year. The MLB team A's appear to be in for another rebuilding year in 2008 after they traded away ace Dan Haren and outfielder Nick Swisher for younger players.
The MLB team A's, though, split eight games with the Red Sox in 2007, and aren't impressed by Boston's postseason success. Regular-season baseball is back in Japan for the first time since 2004, when MLB team Tampa Bay and the MLB team New York Yankees played a two-game set at the Tokyo Dome to open the season. The Chicago Cubs and New York Mets were the first teams to play regular season games in Japan, with a two-game series in 2000.