HOUSTON -- For most of the afternoon on Sunday, Tyson Ross looked like vintage Tyson Ross, his slider dancing and his fastball enticing Astros hitters into weak grounders.
A four-batter stretch in the bottom of the fifth inning was all it took to derail an otherwise resurgent outing for the veteran right-hander. Ross allowed four runs in six innings, three coming when he hung a slider to Max Stassi after consecutive singles to Josh Reddick and Marwin Gonzalez. The Padres dropped the series finale, 4-1, at Minute Maid Park.
"Outside of those three hits, he was borderline dominant," Padres manager Andy Green said. "... There's not really much more we can ask for from our pitching staff this series. All series long, they were outstanding. We've just got to scratch some runs."
• Ross makes beautiful kick save to rob Correa of single
For the second straight game, the Padres fell flat when presented with scoring opportunities. They went 0-for-6 with runners in scoring position on Sunday, and they are hitless in their past 16 at-bats in such situations.
Freddy Galvis and Chase Headley reached base three times apiece, including a second-inning single from Headley that snapped his 0-for-12 skid to start the season. But the Padres didn't muster a hit after Manuel Margot's leadoff single in the fifth. Astros right-hander Charlie Morton struck out seven over six innings.
"We've just got to keep working, man," Galvis said. "We've got to try to get good at-bats, try to get on base. Baseball is baseball. Sometimes you score a lot of runs, sometimes you have series where you don't score too much."
The Padres scored five times over 28 innings in Houston this weekend, four of which came in their victory on Friday night. In contrast, San Diego pitching stifled the defending World Series champs for most of the weekend. Adam Cimber's two scoreless frames gave the San Diego bullpen 10 innings of one-run ball this weekend, the only run scoring on Saturday's bizarre game-ending infield popup.

The rotation did its part, too, with Luis Perdomo, Bryan Mitchell and Ross allowing five total runs. Three of those came in Sunday's fateful fifth frame.
Reddick and Gonzalez singled, then advanced to third on a wild pitch. Ross got Evan Gattis to bounce weakly to second before falling behind in the count against Stassi. With a base open, he tried to come inside with a 2-1 slider. It caught too much of the plate, and the Astros' catcher launched it off the left-field facade beyond the Crawford Boxes.
"It was just poor execution on my part with Stassi," Ross said. "I've got to be smarter than that with a base open."
Otherwise, Ross was excellent. He was certainly sharper than his six-inning, three-run effort on Tuesday, even if the box score won't show it. Ross struck out seven -- five more than his Tuesday start -- and he threw 70 of his 107 pitches for strikes, nine of them swings and misses.

"I threw the ball a lot better today, but the results just weren't what we wanted," Ross said. "There will be a lot more wins if I can throw the ball like that consistently."
MOMENTS THAT MATTERED
Mar-going home: Margot broke out of his prolonged slump in the fifth with a single. The speedy center fielder promptly stole second and advanced to third on Carlos Asuaje's groundout. But -- for the second night in a row -- the Padres put on the contact play, and Margot broke on Eric Hosmer's ground ball to short. Carlos Correa's throw home was perfect, and Margot was tagged out at the dish.

"You take a chance when you put a contact play on," Green said. "The hope is that the ball's to the left or right of the infielder if it's on the ground. When you're not pushing runs across the board, you've got to take those types of chances."
Reddick responds: The Padres clawed a run back in the top of the sixth inning on Austin Hedges' RBI groundout. But Ross couldn't keep the Astros in check, Reddick golfed a 1-1 slider from Ross into the right-field seats. By most standards, it was a decent pitch, just below the knees and on the inside corner of the plate. Ross didn't think so.

"I was trying to go back-door, and it ended up middle-down," Ross said. "That's kind of right in his sweet spot."
QUOTABLE
"I've seen him really, really good, and he was good today. It looked like his ball was moving all over the place. … We had some funny swings. We really had funny swings all series. They did a really good job against us." -- Astros manager AJ Hinch, on Ross
SOUND SMART WITH YOUR FRIENDS
Galvis extended his on-base streak to 10 games with his second-inning single, and he finished 2-for-3 with a walk. The Padres' shortstop is tied with Marcus Semien for the longest such streaks to open the 2018 campaign.
"I'm just trying to do my job," Galvis said. "Every time I get to the plate, I try to get on base. I just want a good at-bat. That's what I can control."
Reigning American League Most Valuable Player Award winner Jose Altuve could've joined that list, but Ross and Cimber combined to keep Altuve off the basepaths in four plate appearances.
ASUAJE ASSUMES LEADOFF ROLE
Asuaje filled the role of leadoff man for the first time this season, and he did the job nicely, reaching base on a seven-pitch walk in the third and an eight-pitch walk in the seventh. Green indicated that he might continue to use Asuaje in the leadoff role with Margot slumping, especially against right-handers.
"Two nice walks today, and he's going to take his swing when he likes his pitch," Green said. "[I'm] just looking for anybody that can kind of ignite us a little bit."
WHAT'S NEXT
The Padres travel to Denver for a three-game series with the division-rival Rockies beginning Monday night at 5:40 p.m. PT. Clayton Richard was hit hard by Colorado last season and again on Wednesday. He'll be looking for a bounce-back effort Monday.
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