Suzuki and Johjima -- both of the Seattle Mariners -- and Iguchi (Chicago White Sox) and Matsui (New York Yankees) are on the ballot for the game, which will be played on July 11 at PNC Park in Pittsburgh.
Suzuki, who was the top overall vote-getter in 2001, entered Wednesday's game against Oakland with a .299 batting average. Johjima, a rookie catcher, was hitting .259 with three home runs and 19 RBIs in 37 games for the Mariners.
Iguchi, a member of the World Series champion White Sox, was hitting .305 with three home runs and 16 RBIs in 34 games.
Matsui, who fractured his left wrist last week and is doubtful for the game, was hitting .261 with five home runs and 19 RBIs at the time of his injury.
Now in its sixth season, the Japanese ballot can be found on MLB.com, any of the 30 club sites, Monster.com and on major.jp, Major League Baseball's official Japanese site.
This is the first year the Japanese ballot will be offered exclusively online.
There were more than 11.5 million votes cast online last year, an increase of nearly one million over the previous year. Fans can vote up to 25 times through June 29, which is when the voting process ends.
The rosters will be unveiled at 7 p.m. ET on Sunday, July 2. The announcement will reveal the 16 elected starters, as determined by fan balloting, and 45 pitchers and reserves, as determined by the player ballot, the two All-Star team managers -- Ozzie Guillen of the White Sox and Phil Garner of the NL champion Houston Astros -- and Major League Baseball.
Fans will have the opportunity to select the final position player for each league's 32-man roster at MLB.com. The Final Vote will provide fans the opportunity to cast their votes from a list of five players from each league over a three-day period. Fans added Roy Oswalt (NL) and Scott Podsednik (AL) to the rosters with that Final Vote last summer.
For the fourth consecutive year, the league that wins the All-Star Game will receive home-field advantage during the World Series. The AL has won back-to-back-to-back Midsummer Classics since that provision was added prior to the 2003 World Series, and eight straight overall.