On a night the Seattle Mariners didn’t get much outside help, they at least helped themselves.

Seattle Mariners’ bullpen has become a surprising strength

Leo Rivas hit a walkoff, two-run home run the 13th inning to lift the Mariners past the St. Louis Cardinals 4-2 Wednesday night. With the win, Seattle kept pace with the Houston Astros and Texas Rangers in the American League playoff race.

The home run came in Rivas’ first at-bat after pinch-running in the 11th inning. It was just his second career home run.

Seattle’s bullpen came up big for a second straight night as it covered 8 1/3 innings and allowed only one unearned run. Emerson Hancock pitched two scoreless innings to earn his first career win as a reliever.

Seattle’s win coincided with the Astros beating the Blue Jays 3-2 on Yanier Diaz’s solo home run in the ninth inning and the Rangers beating Milwaukee 6-3 to finish off a three-game sweep of the MLB-leading Brewers. At 77-68, the Mariners are one game back of Houston for first place in the AL West and 1 1/2 games ahead of Texas for the final wild card berth.

The Mariners did receive a little help when it comes to trying to climb up the wild card standings. The New York Yankees lost 11-1 to the Tigers, and the Boston Red Sox lost 5-4 to the Athletics. Seattle is now 2 1/2 games behind both for the first and second wild card berths.

Elsewhere in the AL playoff race, the Kansas City Royals beat the Cleveland Guardians 4-3. The Mariners are four games in front of the Royals and 3 1/2 games in front of Cleveland in the wild card chase.

Playoff odds

The Mariners have a 84.5% chance of reaching the playoffs and 41.3% chance to win the AL West, per FanGraphs. Houston has 52.3% odds to win the division and Texas 6.3%.

Schedule watch

The Mariners have the 27th-toughest remaining schedule in the league with an opponents’ winning percentage of .471, per Tankathon. Only the Yankees (.469) have an easier remaining schedule among teams in the AL playoff race.

Seattle begins a four-game home series with the Los Angeles Angels (69-77) on Thursday at 6:40 p.m. Mariners right-hander Bryce Miller (4-5 record, 5.53 ERA) is set to take on right-hander José Soriano (10-10, 4.07). Radio coverage begins with the pregame show at 5:30 p.m. on Seattle Sports 710 AM and the Seattle Sports app.

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