NEW YORK -- Carlos Beltran may have accounted for the game-winning run, but in the right fielder's mind there was little doubt about who the star was for the New York Yankees Monday night.

After right-hander Nathan Eovaldi pitched eight outstanding innings, Beltran hit the game-winning sacrifice fly with the bases loaded in the bottom of the ninth and the Yankees picked up a 1-0 victory over the Houston Astros.

"I think the player of the game today has to be Eovaldi," Beltran said. "He just pitched (an) amazing game and he was able to basically shut the opposing team down and allow us for to win this one for him."

Eovaldi remained unbeaten since failing to get out of the first inning June 16 in Miami by scattering four hits. He equaled the longest outing of his career by completing eight innings for the sixth time and second time this season.

"It's unbelievable," Beltran said. "He just feels more comfortable on the mound, more confident. He's been aggressive, attacking hitters with the fastball. When you throw 100 miles per hour, you got to throw the fastball. It's hard to sometimes hit 94, 93 or 95. So imagine when he's throwing 100, 101. The way he's throwing the ball right now, it's been amazing and it's been fun to watch."

In his last 12 starts, Eovaldi is 8-0 with a 2.93 ERA, and this start came five days after he retired the first 16 Minnesota Twins and a day after the Yankees potentially lost veteran left-hander CC Sabathia for the season with a sore knee.

"I felt like I was attacking the hitters really well tonight," Eovaldi said. "Early in the game the slider was working for me and later the split. So I was able to attack the hitters and work out of some jams."

"He was filthy," Yankees catcher Brian McCann added. "He did whatever he wanted tonight."

The other time Eovaldi pitched eight innings this year was July 26 at Minnesota when the Yankees scored seven times. This time, they had six hits in eight innings off right-hander Scott Feldman and also had two inning-ending double plays.

Being unable to push across a run off Feldman ultimately forced the Yankees to win it in the ninth or beyond. They were able to get the win without getting a hit as left-hander Oliver Perez (1-1) issued three straight walks and also threw a wild pitch.

Beltran did not wait long against right-hander Chad Qualls. He drove the first pitch deep enough to center field, and as soon as the ball landed in Carlos Gomez's glove, left fielder Brett Gardner trotted home with the winning run.

"In that particular at-bat, I'm just trying to be as aggressive as I can and hopefully do what just happened," Beltran said. "Try to hit a fly ball deep in the outfield to allow the runner to score. It's good. Today was a great game."

"It's a game we have to win when you have the bases loaded and nobody out," New York manager Joe Girardi said. "The guy that's been coming through a lot in the last two, three weeks came up in that spot and got it done."

Beltran's RBI gave the Yankees their fourth walk-off win and was his first walk-off RBI since he hit a three-run home run off Baltimore Orioles closer Zach Britton on June 20, 2014.

Closer Andrew Miller (2-2) struck out two in the ninth for the win. He gave up a hit to designated hitter Evan Gattis but pinch runner Jake Marisnick was thrown out trying to steal second by McCann

While the Yankees moved into a tie for first place with the idle Toronto Blue Jays, the Astros were shut out for the eighth time this season. Perez's lack of control ultimately resulted in Houston's 16th loss in its last 19 road games.

"I watched the tape and I threw pretty good pitches but I think they were taking all the way because in this stadium, you have to be down in the zone," Perez said. "I threw a lot of sliders close so they could swing at it but they took it."

McCann had half of New York's hits but also was involved in double plays in the fourth and seventh. McCann's base running also thwarted New York's best scoring chance when he was thrown out at the plate by Gomez on a throw that bounced three times before reaching catcher Hank Conger.

The Astros appeared to have their big break with one out in the eighth when third baseman Chase Headley's throw on a ground ball by rookie shortstop Carlos Correa sailed over first baseman Greg Bird's head. After Headley's 20th error, Eovaldi retired right fielder Colby Rasmus and Gomez.

"The atmosphere, this is crunch time for us," Conger said. "So this is nothing new or nothing that we're not expecting."

NOTES: New York 1B Mark Teixeira missed his seventh straight game with a bruised right lower leg, though he said he felt better when he took batting practice from the right side of the plate. Teixeira was on deck as a pinch hitter for 1B Greg Bird in the ninth when Carlos Beltran ended the game with a sacrifice fly. ... The Yankees placed LHP CC Sabathia on the 15-day disabled list and said it is possible he might not return this season from a sore right knee. ... Houston OF George Springer took batting practice on the field for the first time since fracturing his right wrist July 1. He will take batting practice again Tuesday and could start a rehab assignment next week. ... Houston RHP Mike Fiers was named American League Player of the Week for throwing his no-hitter Saturday. Fiers also will be given extra rest and make his next start Saturday against Minnesota on six days' rest.