Logan Gilbert pitched eight scoreless innings as the host Seattle Mariners completed a three-game sweep of the defending World Series champion Texas Rangers with a 5-0 victory on Sunday afternoon.

Rookie Tyler Locklear homered for the Mariners, who won for the seventh time in eight games and increased their lead over the Rangers atop the American League West to 8 1/ 2 games, the largest margin in any division in the major leagues.

Gilbert (4-4) allowed two hits, didn't walk a batter and struck out nine. It was the right-hander's first win in eight starts since May 5 despite a 2.48 ERA in that span.

The only hits Gilbert allowed were a two-out single by Andrew Knizner in the third inning and a two-out double by Nathaniel Lowe in the fourth.

Reliever Austin Voth retired the side in order in the ninth to complete the shutout.

Rangers starter Dane Dunning (4-6) took the loss. The right-hander gave up two runs on four hits in 4 2/3 innings, with three walks and eight strikeouts.

The Mariners scored the first run in the fourth. With two outs, Mitch Haniger doubled into the left-field corner and Luke Raley followed with a run-scoring double into the right-field corner.

Seattle scored again in the fifth after Josh Rojas lined a two-out double to left-center. Dunning's wild pitch bounced off the brick wall behind the plate and caromed toward the Mariners' dugout on the first-base line. Catcher Knizner tracked down the ball and threw to Dunning covering the plate, but Rojas just beat the tag with a head-first slide. The Rangers challenged the call but a video review confirmed Rojas was safe, giving the Mariners a 2-0 lead.

Locklear led off the bottom of the seventh and went deep off reliever Jose Leclerc, the blast landing in Edgar's Cantina on the second deck in left field.

The Mariners added two insurance runs in the eighth after Haniger was hit by a Cole Winn pitch with two outs. Pinch runner Ryan Bliss stole second and, after Raley walked, Dominic Canzone singled to left, scoring Bliss and sending Raley to third. Raley scored on a wild pitch to make it 5-0.