MESA, Ariz. (Interstat) — San Diego State erupted for four runs in the seventh inning and Anthony Marnell IV homered in the eighth to bury Washington State 9-2 in the first game of a Mountain West Conference Baseball Championship doubleheader Sunday afternoon.

The seventh-seeded Aztecs improved to 36-24 while the sixth-seeded Cougars fell to 30-26. Both teams recorded six hits, but San Diego State capitalized on two Washington State errors and eight walks to build an insurmountable lead.

San Diego State starter Drew Talavs earned top honors, pitching 5 2/3 innings of three-hit, shutout baseball while striking out five. He left with a 3-2 lead after allowing only a single and a double in the sixth before Aidan Russell relieved him. Russell worked 3 1/3 innings, surrendering three hits and two runs with four strikeouts.

Washington State starter Brock Blatter kept the Cougars close early, tossing five innings of no-hit ball, but he yielded two runs on a hit batter, a single and a groundout in the first inning. The Cougars tied the game 2-2 in the second when Priest singled, advanced on a throwing error by Talavs and scored on a groundout.

The Aztecs reclaimed the lead in the third. Santana walked, Jackson singled and after a sacrifice bunt, Jabin Trosky delivered a sacrifice fly to center field to make it 3-2.

The game remained tight until the seventh. Kaden Wickersham relieved Blatter and worked a clean sixth, but the Aztecs broke through in the seventh. After two groundouts, Marnell was hit by a pitch, and Zane Kelly doubled to left field to drive him in. Wickersham was replaced by Haider, who gave up an RBI single to Santana, then hit Jackson to load the bases. A walk to Justice forced in another run, and Trosky walked to force in a fourth run. Taber Fast entered and issued a bases-loaded walk to Farrell, making it 7-2.

San Diego State added two more unearned runs in the eighth. Peterson reached on a shortstop error, and Marnell crushed a two-run homer to deep left field for a 9-2 lead. Trevor Stowe closed the eighth with a scoreless inning.

Washington State scratched a run in the eighth on a sacrifice fly by Northrop and another in the ninth on a single by Skjonsby, but Russell shut the door.

Jake Jackson went 3 for 3 for San Diego State, scoring twice. Marnell drove in two with his homer. Trosky finished with three RBIs despite an 0-for-2 day, drawing a walk and a sacrifice fly.

The Cougars’ only extra-base hit was a double by Roy in the sixth, but Talavs stranded runners at second and third by striking out Hartman.

San Diego State’s bullpen combined for 3 1/3 innings of three-hit relief, allowing only the two late runs.

The win gave the Aztecs a measure of revenge after the Cougars had beaten them 14-9 the previous day in the regular-season finale.

Washington State will face San Diego State again in the second game of the doubleheader, with the winner advancing in the tournament. No betting line or over-under was available for the game.