HOUSTON (Interstat) — A critical three-game series between American League West rivals begins Friday night at Daikin Park, with the Seattle Mariners and Houston Astros sitting in a dead heat for playoff positioning.

Both clubs enter the series with identical 84-69 records, adding immense weight to each contest as the regular season enters its final week. The season series has been tightly contested, with the Mariners holding a slim 6-5 edge over the Astros in their 11 meetings so far this year.

The Mariners arrive in Houston fresh off a 2-0 shutout victory over the Kansas City Royals on Thursday. Luis Castillo led the effort with six scoreless innings, followed by strong relief work from Andrés Muñoz and Eduard Bazardo. Seattle has won seven of its last 10 games.

Houston last played on Wednesday, securing a 5-2 win over the Texas Rangers. Cristian Javier delivered six solid innings for the win, and shortstop Jeremy Peña provided a key offensive spark, going 2-for-4 with a home run. The Astros have also found recent success, winning seven of their last 10.

Recent head-to-head matchups have been unpredictable. After the Mariners took two of three from the Astros at home in July, Houston responded by winning a four-game series in May, splitting the first two games before taking the final two.

Projections for the series opener are mixed. The Interstat game simulator predicts a high-scoring affair favoring Seattle, 8-6. However, the same outlet’s ELO rating system gives Houston a slight 50.60 percent probability to win. Betting markets have installed the Astros as a 1.5-run favorite, with an over/under set at 7.5 runs.

Following this series, both teams have challenging final stretches. Seattle returns home for series against the Colorado Rockies and Los Angeles Dodgers. Houston will embark on a road trip to face the Athletics and the Los Angeles Angels.

First pitch for Friday’s game is scheduled for 7:10 p.m. CDT.