SEATTLE — Get ready for a March start to the regular season in 2018.

Major League Baseball released next year’s schedule Tuesday, and all 30 clubs will open the season on March 29. The Mariners will be playing host that Thursday night to the Cleveland Indians at Safeco Field.

Why the early start?

Next year marks the first season under the new scheduling format negotiated in the last labor agreement. It extends the length of the season by adding an additional weekend of play at the start of the season to give each club additional days off.

That means the schedule includes some quirks. For example, the Mariners have open dates on the first two Fridays. All clubs are starting the season on the same date for the first time since 1968.

The schedule is still tentative and subject to adjustments until January. Start times will be announced later, although the Mariners are planning a 7:10 p.m. first pitch for their season opener against the Indians.

The Mariners’ season concludes with seven games at home. The final game is Sept. 30 against Texas. Overall, the Mariners end the season with 19 straight games against AL West opponents.

The interleague rotation matches the Mariners and other American League West clubs against the National League West.

For the Mariners, that means every NL West opponent visits Safeco except Arizona, and they play at every NL West venue except Dodger Stadium in Los Angeles.

The Mariners are matched with Colorado as their “traditional” interleague rival and will play six games against the Rockies: three games at Safeco from July 6-8, and three in Denver from July 13-15.

The Mariners have two-and-two arrangements with San Diego and San Francisco. They play three home games against the Dodgers, and three game at Arizona.

The schedule includes six three-city trips but no four-city itineraries and nothing to match the grind the Mariners endured this August, which included a three-city and a four-city trip.

August is still tough, though, with two three-city trips. In contrast, the Mariners enjoy a home-heavy May schedule with 19 home games and just nine games on the road.

The annual Canadian invasion will occur Aug. 2-5, when the Toronto Blue Jays come to Safeco Field for four weekend games.

The Mariners also have weekend series at home against Boston (four games from June 14-17) and the New York Yankees (three games from Sept. 7-9).

The schedule has the Mariners at home for all three major summer holidays: Memorial Day (May 28 vs. Texas), Independence Day (July 4 vs. the Los Angeles Angels) and Labor Day (Sept. 3 vs. Baltimore).