ST. LOUIS -- The Rockies walked the fine line between competing and evaluating, and righty reliever Yency Almonte made enough of a misstep to swing a lead into a 6-5 loss to the Cardinals on Thursday night at Busch Stadium.

Pitching with a one-run lead in the seventh -- something the Rockies would not be likely to ask of Almonte if in the postseason hunt -- Almonte walked eighth-inning leadoff man Matt Carpenter, then served Dexter Fowler’s two-run homer.

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Almonte then demonstrated some of the ability that earned him the heightened situation by fanning two of the next three batters. But to pass the tests, Almonte knows he has to clean up what happened to the first two hitters, both of whom he fell behind, 2-0.

“I felt like I didn’t capitalize,” said Almonte, in his 27th Major League game over two seasons. “I put myself in bad situations from the get-go. At the end of the day, it’s baseball. I’m supposed to get outs and make pitches. I didn’t do that tonight. After it happened, I told myself I’ve just got to make better pitches and attack.”

While Almonte was having his ups and downs, DJ Johnson, who like Almonte has pitched more at Triple-A Albuquerque than in the Majors, was the rescue option. Johnson pitched the eighth, and with the bases loaded (with two walks sandwiching a Tommy Edman double) and one out, worked a double-play grounder to keep the deficit at one run.

“It’s a situation that all of us want to pitch in -- it’s good to be in high-leverage games, close games,” Johnson said. “Everybody wants to help the team win. That’s what I was trying to do tonight. There was a little bit more traffic than I would’ve liked.”

Johnson and Almonte each pitched a scoreless inning with two strikeouts late toward the end of Tuesday night’s 8-7 loss at Arizona.

“As we move forward, that’s going to be something that we are going to watch -- a lot of our younger pitchers who are coming up -- whether they’re able to handle the everyday test of being a big leaguer," manager Bud Black said. "Tonight, Yency did, DJ did, and we’re going to use our entire bullpen moving forward. But we’ve got to find out some things.”

With Scott Oberg in St. Louis not to pitch but to see vascular specialist Dr. Robert Thompson about a blood clotting problem that has ended his year early for the second time in four seasons, and with veterans Wade Davis, Bryan Shaw and Jake McGee all in periods of struggle for a team 12 games below .500, it’s time for Almonte and Johnson to show they can be depended upon next season, or at some point when standings and game situation spell out the importance.

Add to them Carlos Estévez and Jairo Díaz, who have more experience in higher-leverage situations that Almonte and Johnson. And the Rockies will take a look at righty Wes Parsons, acquired this week from the Braves, in multiple situations. Righty Jesus Tinoco is debuting in the Majors, but he could be fed small doses of pressure situations.

This is also a big time for time for starters Chi Chi Gonzalez (six strong innings at Arizona on Tuesday), Tim Melville (seven impressive innings in a win over the D-backs on Wednesday) and rookie Peter Lambert (who starts against the Cards on Friday). Overall struggles and injuries have resulted in each of them joining the current rotation.

Before auditions under fire began, Nolan Arenado gave the Rockies a 5-2 lead in the fifth with a three-run homer off Cardinals starter Miles Mikolas. And Rockies starter German Marquez was mostly solid for six innings, with six hits and two walks against four strikeouts. But Marquez was victimized by two breaking pitches for two-run homers -- by Marcell Ozuna in the fourth and Paul DeJong to cut the difference to 5-4 in the sixth.