DENVER -- The poor outing of rookie starter Ryan Castellani, who gave up five runs in two innings of a 13-2 loss to the Padres on Sunday afternoon, offered thin cover for the Rockies’ biggest and hardest-to-solve problem -- the lack of a big swing or big inning.

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In Saturday night’s 4-3 victory over the Padres, the lack of lineup punch was less a subject because of starter Antonio Senzatela’s seven strong innings and Daniel Murphy’s pinch-hit, walk-off single. But the Rockies (17-17), who have lost eight of their last 11 at Coors Field, need better offense than the one that bowed to Padres righty Chris Paddack (eight strikeouts in six innings) to break through the forces that hold them at .500.

The Rockies traded for reliever Mychal Givens on Sunday, and he figures to deepen the late bullpen. But until the offense improves, Colorado will be dependent on pitching and defense while other teams take advantage of Coors Field. The Rockies aren’t linked to any big bats on the trade market (then again, they weren’t linked to Givens, and they try to avoid showing up in rumors), so unless something changes before Monday’s 2 p.m. MT Trade Deadline, what they have -- which should be good enough -- is what they have.

General manager Jeff Bridich said he is talking with other teams, but the Rockies’ hitters need to be a big part of the answer.

“It's tough to say right now,” Bridich said, when asked if the Rockies could improve the core of the lineup or add offensively at a position such as catcher. “I think that offensively, there are some better days ahead. We’ve scored a decent amount of runs, if you compare us across the league. But I think everybody knows, internally in particular, that there are, collectively, better days ahead, moving forward with this group.”

But the group has struck too many sour notes lately.

“Guys realize that we’re scuffling a little bit with the bats, and a lot of times players will try to do a little too much, come out of their approach, and it works against them,” Rockies manager Bud Black said. “I thought Paddack today pitched pretty well.

“We won the game last night. The night before [a 10-4 loss] got away from us. But we have to start swinging the bats a little bit better overall.”

San Diego had all the home run swings Sunday, on Eric Hosmer’s three-run shot in the first off Castellani, Jake Cronenworth’s two-run job off Jairo Díaz in the seventh, solo shots from Jurickson Profar and Trent Grisham off James Pazos in the eighth, and Josh Naylor’s 444-foot, two-run pop off Phillip Diehl in the ninth.

In fact, the Rockies have had just one homer (Matt Kemp’s 468-footer Friday night) in the first three games of four with the Padres (21-15), who are ahead of the Rockies and in second in the National League West.

A 5-0 deficit at Coors Field in most years is met with a shrug, but it’s like a big deficit anywhere for the current Rockies -- despite Trevor Story, Nolan Arenado and Charlie Blackmon hitting in the 2-3-4 holes. Their pedigree suggests the Rockies can slug out of any hole. Story struck out four times Sunday.

But in a difficult-to-fathom turn, Arenado’s fourth-inning double (he was left stranded) was the only extra-base hit from the trio this weekend.

None of this is to obscure the importance of pitching. The brightest development was the work of Chi Chi González, who held the Padres to one run and two hits with three strikeouts in four innings. It was González’s first outing since Aug. 3 after a bout on the injured list with right biceps tendinitis.

Castellani has been mostly solid in González’s stead. González has more starter experience, but he also could remain in long relief.

“He was pretty crisp today with his stuff, the ball was down, the slider was good, he moved the ball in and out,” Black said. “It’s a little too early to assess what we’re going to do. But I can’t stress enough, it’s going to take everybody in whatever role they’re in.”

So, González potentially could add to a strength. But to make the most of that strength, the Rockies need to correct their unexpected offensive weakness.