DENVER -- “We believe in that group down there. We’re not going to have anybody else,” D-backs manager Torey Lovullo said of his bullpen following Arizona’s 11-10 loss to the Rockies in 10 innings on Thursday afternoon at Coors Field.

“There’s not going to be a shining star standing outside of our clubhouse tomorrow. It’s them. And I’m going to rely on them, and they know that.”

Moments earlier, Lovullo watched his club get swept by the Rockies, with two of the four losses coming in walk-off fashion. The loss concluded a 10-game road trip through San Diego, San Francisco and Denver over which it went 3-7, dropping below .500 on the season for the first time since April 16.

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The state of Arizona’s bullpen, which faltered in key situation after key situation in Colorado, is one of three key takeaways from the trip:

1) The bullpen remains chaotic

It seemed as though Archie Bradley had turned a corner after a rough start to May with three consecutive scoreless outings coming into the series with the Rockies. But he surrendered a game-tying, two-out, two-run single to Nolan Arenado in the seventh inning of Monday’s 4-3 walk-off loss.

The following night, Bradley struggled again, walking the bases loaded and giving up a two-run double to Ryan McMahon that extended the Rockies’ lead to 6-2.

As goes Bradley, so goes the D-backs’ bullpen. He serves as the linchpin of the relief corps, getting the ball from the middle innings to closer Greg Holland when everything is running smoothly. When it’s not, disorder is the order of the day.

Yoshihisa Hirano was charged with the two runs that scored on Arenado’s single against Bradley on Monday. And after the D-backs put a five spot on the board in the eighth to grab a 10-8 lead Thursday, the most reliable reliever at Lovullo’s disposal of late, Yoan Lopez, couldn’t hold it.

Bradley said that after his latest outing, he was “clueless” as to what was going haywire, but by spending extra time in the video room, he’s identified some mechanical issues that need to be addressed.

He also said there’s only one way to stop the runaway train that is the D-backs bullpen.

“It’s the easiest thing to say, and it’s the hardest thing to do.” Bradley said, “But it’s sticking to what you’ve been doing. I think there’s a time when you take a step back and look at what’s causing some of these things.

“But at the same time, you’ve gotta play catch the right way, look at video, there are some things that you just have to do. It’s tough, because sometimes the results don’t happen, and when you mess up, everyone sees it. The whole team feels it.”

2) The starting rotation is shrouded in uncertainty

When Luke Weaver strained his right forearm during a start against the Giants last Sunday, it was the latest in a series of blows to the D-backs’ starting rotation.

Taijuan Walker was on track to soon make his return from Tommy John surgery, but had a setback and is sidelined with a strained right shoulder capsule. Then Zack Godley’s 7.71 ERA as a starter resulted in a move to the bullpen.

Beyond Zack Greinke, Robbie Ray and Merrill Kelly, there are two spots that need to be filled, one of which may or may not be for a long period of time, depending on what Weaver is told after seeking a second opinion.

Among the candidates to fill those slots are two rookies, one of whom has gotten three starts already, including Thursday, when he gave up five runs in two innings. Taylor Clarke pitched well over his first two career starts, but faltered in his first Coors Field experience.

Lovullo is taking things one turn through the rotation at a time, and said Jon Duplantier will start the series opener against the Mets at Chase Field on Friday. The right-hander posted a 2.25 ERA in five outings for Arizona, but has a 4.76 ERA in six starts for Triple-A Reno.

3) Lineup on a rollercoaster ride

The bats were cold to open the road trip in San Diego, and exploded to life when the D-backs scored 34 runs over three games in San Francisco. But over the first three games of the series at Coors Field, they averaged three runs as a result of an inability to hit with runners in scoring position.

Then on Thursday, Arizona was 4-for-6 in that situation, and scored 10 runs on 16 hits. With the vulnerability of the pitching staff at the moment, the production will need to stabilize.

“These guys are frustrated,” Lovullo said. “I think that frustration kind of motivated them and drove them to be ready. … A lot of good things happened. We had a lot of hits, some clutch home runs, Christian [Walker] swung the bat well.

“We’re coming home, and we’ve gotta get right in a couple areas. And we will.”