Kyle Freeland upheld his leg of what the Rockies want to be a starting pitching relay to the end of the season.

Freeland pitched six scoreless innings Monday night against the Padres -- who lead the Major Leagues in runs -- in the opener of three key games at Petco Park. The Padres, however, walked off against the Rockies, 1-0, on Jurickson Profar’s RBI double off Carlos Estévez in the ninth inning.

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Because Freeland’s effort -- six strikeouts against three hits and three walks -- added to a growing trend of solid starting pitching, the Rockies (20-21) were surprisingly upbeat even though the loss dropped them below the threshold for the eight-team National League postseason. After all, those standings are volatile; the Rockies woke up Monday in seventh.

But if the starting pitchers are steady, the Rockies expect it to work out in the end.

Freeland was matched against Padres starter Dinelson Lamet, who fanned 11 and allowed six hits in 7 2/3 innings.

“You’ve got to pitch to win,” Rockies manager Bud Black said. “There are going to be nights like tonight where you get shut down by a good pitcher, and you’re going to have to stay in the game. And you stay in games by pitching and playing good defense. We’re capable of that.”

Freeland’s work, which included forcing a Profar grounder with two on to end the fourth and fanning Manny Machado and Mitch Moreland to end the fifth with a runner at third, came after a two-start slump (eight runs and 19 hits in just 6 1/3 innings). Monday marked the seventh quality start (six or more innings of three or fewer earned runs) in the left-hander’s nine outings.

During the Rockies’ recent 2-4 homestand, which included three losses to the Padres, the rotation struggled, along with the rest of the club. But four games into the current road trip, which started with taking 2-of-3 at Dodger Stadium, the Rockies have received solid-to-standout work from three of their starters.

“We can rely on them if we’re facing someone tough that day,” said shortstop Trevor Story, who scratched out two hits. “‘Free’ did his thing all night, kept us in the game.”

Antonio Senzatela held the Dodgers to two runs in 5 1/3 innings, only to see relievers give up four home runs in a 10-6 loss on Friday. He has given up two or fewer runs in six of his eight starts.

Germán Márquez held a vaunted L.A. lineup to two runs in seven innings Saturday, a game the Rockies won late, 5-2. The only step back during this turn was rookie Ryan Castellani’s on Sunday against the Dodgers, but the Rockies rallied to win, 7-6.

Righty Chi Chi González will take the baton Tuesday against the Padres.

“We’ve got to feed off one another,” Freeland said. “Even though tonight was a tough loss, Chi Chi’s got to feed off what the pitching staff did tonight.”

High pitch counts in the fourth and fifth innings ultimately shortened Freeland’s outing. Some of it was due to his not getting calls on some close pitches. But also, Freeland was facing the Padres for the third time. He used changeups at a high frequency while blanking them for six innings on Aug. 1. Freeland noted the Padres “sat soft on me” on Aug. 28 and pushed him out after 4 1/3 innings.

Like Márquez, who had slumped before his strong Dodger Stadium outing, Freeland made minor mechanical tweaks, with the confidence that his form would return.

This time, Freeland went fastball/slider and kept the Padres off the scoreboard while keeping up with Lamet.

“It’s always fun pitching in those pitchers’ duels -- you really don’t see them a whole lot anymore,” Freeland said. “You throw up a zero, then you’re like, ‘All right, your turn.’ It’s fun to do that, battle against another pitcher knowing that you guys are both locked in.”