(Photo credit: Joe Nicholson-USA TODAY Sports)

George Kirby pitched six scoreless innings as the Seattle Mariners defeated visiting Texas 1-0 in the regular-season finale Sunday afternoon, spoiling the Rangers' bid to claim the American League West title.

The loss leaves the Rangers (90-72) leaves in a probable tie with Houston atop the division as the Astros held an 8-0 lead over the Arizona Diamondbacks through seven innings. Texas lost the tiebreaker based on the season series between the clubs (the Astros went 9-4 against their Lone Star State rivals).

If the result holds, the Rangers would head into the playoffs as the AL's second wild-card team and travel to Tampa Bay for the opening round.

The Mariners (88-74), who were eliminated from postseason contention Saturday, finished third in the AL West. Seattle would finish a game behind Toronto for the third and final wild-card berth if the Blue Jays lose Sunday.

Kirby (13-10) allowed three hits. The right-hander didn't walk a batter and struck out seven.

Kirby retired the first eight batters he faced before Evan Carter doubled to right field with two outs in the third. The only other hits Kirby allowed were a two-out single by Adolis Garcia in the fourth and a one-out single to Jonah Heim in the fifth.

Rookie right-hander Prelander Berroa, called up from Double-A Arkansas earlier in the day, relieved Kirby and struck out both Garcia and Nathaniel Lowe in the seventh.

Trent Thornton pitched a 1-2-3 eighth and Isaiah Campbell worked the ninth for his first career save despite allowing a leadoff single to Carter.

The Mariners opened the scoring in the bottom of the fourth off Rangers starter Dane Dunning. With one out, Eugenio Suarez grounded a single into center field, Jarred Kelenic lined a single to left and

Ty France walked to load the bases. Lefty Martin Perez relieved Dunning and got Dominic Canzone to hit a soft grounder to first baseman Lowe, who stepped on the bag and threw home in an attempt to turn an inning-ending double play. Catcher Heim's blind swipe missed as Suarez slid safely under the tag.

Dunning (12-7) allowed one run on four hits over 3 1/3 innings. The right-hander walked one and struck out four.