After playing in the 2019 Major League Baseball Opening Series in Japan against the Oakland Athletics March 21-22, the Seattle Mariners will open their home season with a four-game series against the Boston Red Sox. Opening Night is set for Thursday, March 28 at 7:10. The series continues through the weekend, and the first homestand concludes with two games against the Los Angeles Angels (April 1-2). The only other time the Mariners and Red Sox faced each other in a season opener was in 2000, which was also the first regular season opener at Safeco Field.
The Mariners today released the 2019 tentative regular season schedule. Major League Baseball earlier today announced the 2019 tentative schedules of all 30 teams.
MLB Opening Series in Japan: "A great opportunity to promote Seattle as a leading destination"
For the second time this decade, the Mariners will travel to Japan to open the regular season against the A's in the Tokyo Dome. Tom Norwalk, President & CEO of Visit Seattle, said, "When the Mariners made the same trip to Japan in 2012, we took advantage of a great opportunity to promote tourism in Seattle. It was very successful, and we plan do so again in 2019." 
"Japan is one of our most important and longest-standing markets for both trade and overseas tourism. The games and events in Tokyo provide us with a perfect way to connect with our key travel buyers, media and consumers…..through the magic of Mariners baseball…..and to continue to build awareness of Seattle as a must-visit destination," said Norwalk.
In addition to the two regular season games in Tokyo, the Mariners play two exhibition games against Japanese league teams (March 17-18). 
Interleague Play
American League West Division teams will meet National League Central Division teams in Interleague Play in 2019. The Mariners first home interleague matchup will be April 30 and May 1 against the Chicago Cubs. The St. Louis Cardinals come to town for three games July 2-4, and the Cincinnati Reds round-out the home interleague schedule with three games in Seattle September 10-12.
The Mariners will travel to Milwaukee to meet the Brewers June 25-27, visit Chicago for a two-game series against the Cubs at Wrigley Field September 2-3, and meet the Pirates for three games in Pittsburgh September 17-19.
There are also two road and two home games against the National League West Padres at San Diego April 23-24 and in Seattle August 6-7.
Schedule Notes of Interest
• The Mariners will be home for two of the three major summer holidays: Memorial Day, May 27 vs. the Rangers and July 4 against the Cardinals.
• The New York Yankees come to town for three games August 26-28.
• In their first 18 home games, March 28 through May 1, the Mariners have three series against American League West rivals (Angels, Houston Astros and Texas Rangers) and three against teams currently in first place in their respective divisions (Red Sox, Cleveland Indians and Cubs).
• The 2019 season ends with a six-game homestand against division rival Astros (September 24-25) and the Athletics (September 26-29).
The full 2019 Mariners tentative schedule, with home start times, is available now on Mariners.com. The complete 2019 MLB tentative schedule of all 30 teams is available on MLB.com.
Start times for Mariners road games will be released later. The schedule is subject to change until it becomes official in January, 2019.