The Seattle Mariners have been waiting to get some outside help in the American League West race race. It finally happened Sunday.

And now the Mariners stand alone atop the division at the latest point in any season since 2001.

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The Mariners walloped the Los Angeles Angels 11-2 to complete a series sweep and a perfect homestand for their ninth straight win Sunday. That came after the Houston Astros fell 8-3 to the Atlanta Braves earlier in the day, opening the door for Seattle to move out of a tie with their rivals in first place in the AL West.

The M’s also have some more distance between them and the Texas Rangers, who went down 5-2 against the New York Mets on Sunday.

It was the first time since Sept. 2 that the Astros and Rangers lost on the same day.

The Mariners are now 82-68 on the season and have sole possession of first place in the AL West for the first time this season since June 2. They’re a game ahead of the 81-69 Astros, who have lost nine of their last 15 games, as well as three games in front of Texas (79-71). The Mariners, who last won a division title in 2001, hold the season tiebreaker over the Rangers.

Seattle entered Sunday tied with Houston for first in the division for the third straight day. The M’s, Astros and Boston Red Sox (81-68) were also tied for the second and third wild card berths entering Sunday. Boston plays Sunday night against the New York Yankees (83-65), who hold the top wild card spot.

According to FanGraphs’ playoff odds, the Mariners’ odds of winning the division after Houston’s loss Sunday was 63.4%. Their odds of making the playoffs moved up to 94.8%.

The M’s will have a chance to gain even more ground on either the Astros or Rangers starting Monday as Seattle’s two AL West rivals begin a three-game series in Houston.

Seattle will start a three-game series at Kansas City on Tuesday, then play a three-game series in Houston beginning Friday. The winner of that series will clinch a potentially important season tiebreaker between the two teams.

Seattle Sports’ Zac Hereth and Brent Stecker contributed to this post.

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