HOUSTON -- It seems foolish to grouse about fastball command when Astros right-hander Lance McCullers unleashes the overwhelming knuckle curveball he wielded on Monday, but wrangling his fastball is all that stands between McCullers and complete and utter dominance.

McCullers delivered a masterful performance coming off a missed turn in the rotation while George Springer supplied the offense in the Houston Astros' 2-1 win over the Seattle Mariners at Minute Maid Park.

McCullers (4-2) produced his best performance of the season, working seven overpowering innings in his first start since June 22. He allowed one run, five hits and one walk with a season-high-tying 10 strikeouts.

"He really had his breaking ball," Astros manager A.J. Hinch said of McCullers. "And when he has his breaking ball on it's as electrifying a pitch as we have on this staff and also in the league. When he learns a little bit more fastball command he can be even more dominant than he was today, but his breaking ball was pretty incredible today."

Sidelined by a blister on his right index finger last week against the Angels, McCullers pitched with impressive efficiency against Seattle (43-40).

He retired 14 consecutive Mariners during the middle stretch of his outing and also danced around trouble in the first and seventh innings.

The Mariners placed runners at third base with no outs against McCullers twice yet came away empty both times.

Leonys Martin smoked a leadoff triple to center in the first inning yet ran into a 2-3-1 double play while trying to score after Astros catcher Jason Castro threw to first base to complete the strikeout on Robinson Cano. Marwin Gonzalez followed with a throw home to McCullers, who applied the tag.

McCullers allowed the first three batters to reach base in the seventh inning before wiggling his way out of danger to protect his one-run lead. Seattle first baseman Dae-Ho Lee, whose RBI single in the second inning scored Kyle Seager, hit a sharp grounder back to the mound that McCullers fielded before throwing home to start a 1-2-3 double play.

McCullers followed by inducing a lineout to left field from Adam Lind, capping his 94-pitch masterpiece.

"I thought we had them on the ropes there in the seventh inning, bases loaded and nobody out," Mariners manager Scott Servais said. "Unfortunately, we didn't get it done. But McCullers had really good stuff. Probably one of the better breaking balls we've seen all year."

Said McCullers: "That was huge, and that was the game right there, 2-1 (score). You pitch the whole game to face two or three batters and I came out on top that time."

"The Astros (44-39) struck quickly off Mariners left-hander Wade Miley (6-5) in the bottom of the first, with Springer stroking a leadoff double to left-center field and later scoring when third baseman Luis Valbuena lifted a sacrifice fly to Martin in center with the bases loaded.

Miley surrendered five hard-hit balls in the first but just one run and he settled in soon thereafter, allowing just three runners over the ensuing three innings before Springer stepped to the plate in the fifth.

Ahead 1-0 in the count, Springer drilled his 19th home run to left-center to push the Astros back in front. Miley surrendered two more hits but pitched effectively before departing with two outs in the seventh, allowing two runs on seven hits, two walks with two strikeouts.

"I tried to get a sinker down and away and cut it back over the plate," Miley said. "I just made a mistake pitch and he (Springer) did what he's supposed to do with it.

"I kind of got lucky to get out of that first inning only giving up one. I was just trying not to think too much and just go out there and try to compete."

NOTES: Simone Biles, a four-time U.S. all-around gymnastics champion and native of Houston suburb Spring, tossed a ceremonial first pitch prior to the game. Biles will represent the United States in the 2016 Olympic Games in Rio next month. ... Mariners RHP Felix Hernandez will throw a simulated game on Wednesday. Hernandez, placed on the 15-day disabled list on June 1 with a right calf strain, is scheduled to work three 15-pitch innings before the series finale against the Astros. ... Mariners RHP Taijuan Walker, scheduled to start on Tuesday, remains under close observation as he continues to deal with right foot tendinitis. Walker pitched effectively against the Orioles on June 30 in his first outing since having his spot in the rotation skipped. ... The Astros took batting practice on Monday, a rarity for a day game.