SEATTLE -- Luis Castillo flashed his big boyish grin as Mariners manager Scott Servais paced to the mound with two outs in the seventh inning on Friday night. ¡°La Piedra¡± had just issued a two-out walk on his season-high 104th pitch and knew his night was done.

But even in a moment that¡¯d be frustrating for most, having an otherwise brilliant outing end with a free pass of all outcomes, Castillo couldn¡¯t help but exhibit that ¡°positive mentality¡± that he almost always references after each outing, good and bad.

Because that¡¯s truly ¡°La Piedra¡± -- in peak form.

¡°That's 'The Rock' -- he wants to stay in there as long as he can,¡± Servais said. ¡°He never gets upset or angry about it. He'll always have a smile on his face.¡±

Castillo¡¯s one-run gem, in which he carried a no-hitter into the sixth inning, lifted the Mariners to a 2-1 win as Blue Jays fans flocked from north of the border in their annual summer invasion of T-Mobile Park. Seattle¡¯s offense gave him just enough run support to secure its second straight win. And a gritty effort from relievers Austin Voth, Ryne Stanek and Andr¨¦s Mu?oz -- along with a remarkable barehanded play from Josh Rojas in the ninth -- helped lock it down.

It¡¯s been a mostly up but occasionally down year for the Mariners¡¯ two-time Opening Day starter, who hasn¡¯t quite matched the dominance that he exhibited over his first two seasons in Seattle, and as such, likely won¡¯t be heading to his fourth All-Star Game on July 16 in Arlington.

Still, as the Mariners navigate what¡¯s been their most tumultuous offensive stretch of the season, the value of performances like Friday¡¯s can¡¯t be overstated -- especially as the Astros continue to climb their way up the American League West standings. Houston held on to a 13-12 win in Minnesota, but only after surrendering seven runs in the ninth. With it, the Astros remain two games back of the first-place Mariners and are 2 1/2 games back of the final AL Wild Card spot.

Castillo¡¯s lone blemish on Friday was also the first hit against him -- a one-out solo homer that Kevin Kiermaier blasted 379 feet into the right-field bleachers. Spencer Horwitz immediately followed with a single. But those represented the only knocks against Castillo, who also had an additional walk beyond the one that ended his night.

He struck out eight of the 23 batters he faced -- including Blue Jays star Vladimir Guerrero Jr. thrice, a feat that only Houston¡¯s Ronel Blanco could claim this season before Friday.

Both he and Seattle¡¯s coaching staff believe it was the overhaul of his slider, which featured a new grip and a 3.3 mph dip in velocity from his season average of 86.2 mph, that made the difference.

¡°It gives me three different varieties of speed to play with the batter,¡± Castillo said through interpreter Freddy Llanos, when pairing with his two fastballs and changeup.

Castillo tweaked the slider after a consultation with Mariners coaches Pete Woodworth and Trent Blank, and he said the early returns in the bullpen pregame were middling. That¡¯s what made its effectiveness in-game all the more impressive.

¡°The catcher didn't even move,¡± Castillo said, laughing. ¡°It just went straight. ... But I think with this new one and the old one that I have, we can do a little mix and match on it.¡±

The Mariners¡¯ bats, meanwhile, again experienced more strikeout struggles, fanning 13 times -- including 10 against splitter specialist Kevin Gausman, whose only two clean innings were the fifth and sixth to finish his outing strong. Luke Raley, who was robbed of extra bases by a remarkable catch from left fielder Daulton Varsho in the first, got payback in the third with a two-run double, which represented Seattle¡¯s only scoring.

It plated Cal Raleigh, who drew a two-out walk after falling into a 1-2 count, and Julio Rodr¨ªguez, who legged out an infield single -- but only after a successful Mariners challenge. That decision, from replay coordinator Andy Bissell, arguably won them the game, because had Rodr¨ªguez been out, it would¡¯ve ended the inning, and the Mariners obviously went scoreless the rest of the way.

¡°He nailed it,¡± Servais said. ¡°That was the best call of the night.¡±

They finished with eight hits but also went 1-for-9 with runners in scoring position and stranded 12 baserunners. Their struggles to cash in have been well-chronicled, but thanks to Castillo and the bullpen, that¡¯s a story for another day.