The 25-year-old right-hander was pitching on the day the Yankees learned Sabathia, the 2007 Cy Young Award winner, was put on the disabled list with right knee inflammation. New York had also just come off a deflating series in which they lost three of four to Cleveland.
"Of course it's on my mind, CC going down," Eovaldi said. "I know I needed to be able to step up tonight, help out the bullpen."
With a devastating slider, new-found splitter and fastball that topped out at 101 mph and reached 100 in the eighth, Eovaldi gave up only four singles and walked three. He is 13-2 with a 4.00 ERA in his first season in pinstripes after going 6-14 last year for Miami.
Catcher Brian McCann attributes Eovaldi's success to the development of a splitter this season.
"It's a game-changer," McCann said of the pitch that dives late. "He was filthy. He did whatever he wanted tonight."
Oliver Perez (0-1) relieved Feldman and gave New York fans a reminder of his wild five seasons with the Mets. He walked Brett Gardner, threw a pitch to the backstop, then walked Alex Rodriguez intentionally. McCann walked to load them and end Perez's night.
"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 and I threw a lot of sliders close so they could swing at it, but they took it," Perez said.
Beltran then gave Chad Qualls' first pitch a ride to deep center field for New York's fourth walk-off win this year.
The AL West leaders lost for the 18th time in 22 road games. The Astros were coming off a sweep of the Los Angeles Dodgers at Minute Maid Park.
Houston dropped to 19-21 in one-run games.
"These are exciting games. I wish we would have won," manager A.J. Hinch said. "One-run games are tough losses, but you'll see tomorrow that we're a resilient team. We'll bounce back and be better."
Each team had its chances, with the McCann getting thrown out at home plate by center fielder Carlos Gomez to end the seventh.
McCann led off the inning with a single and Beltran hit a sharp line drive off the wall in right field to put men at first and third with none out.
Greg Bird struck out, then Chase Headley hit a fly to center. McCann tried to tag, but Gomez made a strong throw that reached catcher Hank Conger on three skips. Conger caught the relay as he was falling to his knees and reached in front to tag a sliding McCann for the double play. Conger pumped his fist and shouted as he sat near home plate.
Astros: OF George Springer (broken right wrist) took early batting practice, his first BP since getting hurt July 2. "It was good to see him on the field," Hinch said. "I joked with him he looked like a real player again." Springer will hit again Tuesday and probably on Wednesday before deciding on how soon he plays rehab games. ... Hinch said Jed Lowrie's hand is fine, and that the infielder was due an off-day Monday.
Yankees: 1B Mark Teixeira (bruised right shin) was out for his seventh straight game. He's starting to feel better, though, in all aspects except running. "The running is still a little bit of a struggle," he said. He was on-deck to pinch hit in the ninth.
Gardner celebrated his 32nd birthday by scoring the winning run.
Astros: LHP Dallas Keuchel (14-6) might be the best-suited pitcher in baseball for homer-friendly Yankee Stadium. He leads the majors with a groundball-to-flyball ratio of 4.53. He shut out New York in Houston on June 25.
Yankees: Ivan Nova (5-5) is coming off a loss to Cleveland in which he allowed three runs and six hits in a season low-tying five innings. He's only faced the Astros once, in his first start last season. Three starts later, the right-hander's year was over due to Tommy John surgery.
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