CINCINNATI -- Although they lost the series finale at Milwaukee on Wednesday, the Reds still rode into an off-day and then Friday night having taken two of three from the Brewers. For those wondering if this would finally be the point when the wind got behind Cincinnati’s back, that boost was certainly missing against the Rockies in the series opener at Great American Ball Park.

In the 12-2 loss to Colorado, the Reds’ offense didn’t muster enough against German Marquez as the Rockies right-hander pitched seven strong innings. But the real surprise was that Cincinnati ace Luis Castillo wasn’t the usual fail-safe to keep the game tight.

“It’s not the day Luis normally has had or is going to have the rest of the year,” said catcher Tucker Barnhart, who returned from the injured list on Friday after missing a month of action.

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In a rare dud of an outing for Castillo, he gave up a season-high six earned runs over five innings and tied his season high in hits (eight) and home runs allowed (two) while walking two and striking out six. It was only the fourth time in 21 starts in 2019 that he gave up more than three earned runs.

Seeing Castillo not perform well was weird. But it wasn’t like he was ineffective. Of his 97 pitches, he still got 21 swings and misses -- including 11 of 36 changeups.

“Luis, we’ve seen him so good, so many times out this year,” Reds manager David Bell said. “But these games are going to happen. It seemed like it was their approach, being aggressive and trying to get to his fastball. I know he’ll be anxious to get back out there next time.”

The first three runs came quickly when a one-out walk to Nolan Arenado in the first inning preceded a three-run homer to right field by Daniel Murphy off a 97-mph first-pitch fastball. Murphy was expecting that pitch there.

"Luis has been throwing the ball really well. I saw on the video, he seems really comfortable out there and is really coming into his own,” Murphy said. “He's got the electric fastball and the changeup can be pretty devastating. I happened to get a heater in the middle of the plate 0-0, and put a pretty good move on it and we were off and running then."

Castillo settled in for a stretch until the fourth inning when Charlie Blackmon hit a two-out RBI double to the left-field corner. The next batter, David Dahl, attacked a 2-2 fastball for a two-run homer. Coming into the night, Castillo had only once previously given up a homer with runners on base this season, to Buster Posey of the Giants on May 5.

“It looked to me that they didn’t want to get to two strikes,” Barnhart said. “Why would you want to get to two strikes against a guy like him? They did a good job. Charlie Blackmon spoiled a really good changeup in the first at-bat of the game. That was kind of the way the game went.”

The last time Castillo gave up six earned runs in a start was March 31, 2018, vs. the Nationals during his first game of that season.

“The two homers cost me the game. I think I made good pitches,” Castillo said via interpreter Julio Morillo. “They put good swings on the ball. They are big-league hitters, right? I think they put good swings on the ball and homered.”

Castillo, a first-time All-Star this season, dropped to 9-4 with a 2.71 ERA.

“My outings lately have been really good outings,” Castillo said. “Of course, I want to stop this now and don’t carry it over into the next outing. Sometimes they win. They beat me today. I’m just going to keep working hard in order to be better for the next one.”

The Reds got one run back in the first when Jesse Winker hit a leadoff double, went to third on a Marquez balk and scored on Joey Votto’s groundout. Leading off the Reds’ second, Josh VanMeter slugged his third home run in his last four starts by hitting a 2-1 Marquez pitch over the center-field fence that made it a 3-2 game.

But the Reds got no closer than that and Colorado added six runs in the ninth off struggling reliever Jared Hughes.

“We have to bounce back from this and go out and play well the rest of this series,” Bell said.

Now nine games under .500 at 46-55, matching its season-high deficit, Cincinnati’s elusive hopes to catch a breeze and make a move in the National League Central continued to prove elusive.

The Trade Deadline looms on Wednesday at 4 p.m. ET, and if the Reds don’t play well, it could become harder to justify being serious buyers.

“I think sooner rather than later we’re going to start winning some games. Unfortunately, we haven’t been going on a run lately,” Castillo said. “You have to see the positive things. I think we’ve gotten better as a team. You have to see the positive and not focus on the negative things.”