ST. LOUIS -- Earlier this week, Padres manager Bob Melvin said that he was encouraged by the amount of base traffic the offense was generating, and that with a big hit or two, the club’s recent struggles might become a thing of the past.

As it turns out, the Padres still haven’t found what they are looking for.

San Diego had three opportunities to change the outcome of Wednesday’s 5-2 loss to the Cardinals and came up empty each time.

“It’s just one of those things where we're just falling a little bit short,” Melvin said. “It's frustrating for us, but you just keep working to keep fighting your way out.”

The first chance came in the first inning, after the Padres started the game by grabbing a quick 1-0 lead on back-to-back hits by Jurickson Profar and Manny Machado. San Diego came inches away from putting up a crooked number, but Ha-Seong Kim was robbed of a potential two-run, two-out hit by a diving catch on a sinking line drive from Cardinals center fielder Harrison Bader.

“It's a terrific center fielder there, one of the best in the league -- if not the best,” Melvin said.

The Padres’ second chance came in the seventh inning, when they had runners on the corners with two outs. But Trent Grisham was called out on strikes to end the frame.

San Diego didn’t go quietly, loading the bases in the ninth after Luke Voit had already smashed a 420-foot solo homer to right-center to narrow the deficit to 3. Pinch-hitter Robinson Canó’s deep line drive looked like a hit off the bat, but it was chased down by Cardinals left fielder Corey Dickerson to end the game.

“I hit the ball good,” Canó said. “It was a changeup middle away. I hit it pretty good, and it ended in their favor.”

Wednesday was a season-high third straight loss for the Padres, who were swept for the first time this year. San Diego has lost seven straight at Busch Stadium after being swept during its lone trip to St. Louis last season as well.

“I don't think we’ve had a losing streak like this yet, so it's something we're not used to,” Voit said. “But these guys are a resilient bunch of guys, and we’ll flip it around and get it going.”

The Padres have scored three or fewer runs in 26 of their 50 games this season and are 10-16 in those contests. They didn’t score more than three in any of these three games against the Cardinals and have scored just 22 runs in their last nine contests.

Part of the issue in coming up with that big hit, at least over the last two days, has been a lack of opportunities.

After a rocky opening frame, Cardinals starter Dakota Hudson silenced the Padres’ bats, retiring 18 straight hitters until a Jake Cronenworth single in the seventh.

“Dakota got into a groove there,” Voit said. “... He’s a ground-ball pitcher, he's getting a lot of soft contact and, you know, he was effective.”

The Padres left just four men on base in innings one through seven, stranding a pair in the first and last of those frames. This, after stranding just three during those first seven innings the night before.

“We had a couple good at-bats, the first two at-bats of the game were really good. [It] felt, you know, a little different offensively,” Melvin said. “And we had some momentum and just couldn't follow it up until the ninth again. Our best at-bats are coming later in the game, but at this point right now during the stretch here we're in, we're just falling short.”

Padres starter Yu Darvish allowed five runs in 7 2/3 innings. His biggest mistake was missing his location on a 94.2 mph fastball to Nolan Arenado, who drove it over the left-field wall for a go-ahead two-run homer that gave the Cardinals their decisive lead in the sixth.

“When you're dealing with a small margin of error, with the offense not scoring many runs,” Melvin said, “it makes it a little bit more difficult.”