SEATTLE — The pitch was perfect. The punctuation was, too.
Luis Castillo, on a 3-2 pitch, painted a 96.8-mph fastball on the outer edge to strike out Oneil Cruz looking to end the top of the seventh inning Saturday night.
Castillo then spun around the mound, holding a pose for a beat, and then walked backward for several steps as he flashed his trademark fist pump, a smooth celebration for the veteran right-hander’s best performance of the season.
The Seattle Mariners needed Castillo at his best, too.
Rookie Ben Williamson’s two-out double drove in Jorge Polanco for the game’s only run in the sixth inning, and the Mariners eked out a 1-0 victory and series win over the Pittsburgh Pirates before a crowd of 32,295 at T-Mobile Park.
Matt Brash and Andrés Muñoz locked it down late to complete the two-hit shutout, and the Mariners (47-42) posted back-to-back shutouts for first time since last August.
Pirates starter Mike Burrows threw five shutout innings, working around four walks (three to Cal Raleigh) with six strikeouts.
The Pirates turned to lefty reliever Caleb Ferguson in the sixth inning, and Polanco greeted him with a leadoff double down the left-field line. Polanco moved to third on Luke Raley’s broken-bat groundout to first base.
Pinch-hitter Donovan Solano worked a 3-2 count but ended up grounding out. Williamson then came through with a sharp double to the wall in right-center field.
