ST. LOUIS -- The additions that the Cubs made over the past few days, and even dating back to June with the signing of closer Craig Kimbrel, showed a belief from the front office that the club has the ability to turn this turbulent season around. That begins and ends with getting things in order on the road.

On Thursday night, the debuts of Nicholas Castellanos and Tony Kemp -- a pair of trade acquisitions one day earlier -- were marred by another disappointing defeat away from the comforts of Wrigley Field. Jack Flaherty flirted with a no-hitter for the Cardinals and the Cubs exited Busch Stadium after an 8-0 loss and another series defeat.

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"It is hard not to be frustrated with our performance on the road," Cubs general manager Jed Hoyer said on Wednesday. "We go on the road, we dip into a slump, we struggle, we lost a lot of close games. We come back home, we feel better about things. It's just been a very frustrating cycle for everyone -- the players, the coaches, the front office.

"Seeking out why we are the team we are at home versus the team we are on the road has been something we've really been scratching our heads about."

With the loss, the Cubs ended their three-city swing through San Francisco, Milwaukee and St. Louis with a 3-6 record (one win and two losses at each stop). Overall, Chicago now has a 21-33 record on the road with a National League-low .389 winning percentage. The North Siders have not won a road series since taking two of three from the Nationals on May 17-19.

In the past 10 road series, Chicago is now 0-9-1.

Cubs manager Joe Maddon said he has been unable to pinpoint the specific problem.

“I wish I could. I don't have an answer for you -- I don't,” Maddon said. “I honestly don't have a solid opinion -- I don't. I normally do, but I can't put my finger on this one. It's perplexing.”

Cubs starter Jon Lester agreed.

“No idea. If I knew, we'd fix it,” Lester said. “I can't answer it. Obviously, we like Wrigley and we don't like anywhere else.”

Remarkably, the Cubs remain just one game behind the first-place Cardinals in the NL Central even with the woes outside Wrigley. That is due to how well the Cubs play in front of their home audience. Beginning Friday, Chicago is set to host the rival Brewers at the Friendly Confines, where the Cubs have gone 36-18 this season. Only the Dodgers have more wins at home in the NL in 2019.

Flaherty was the catalyst behind the Cubs’ road issues on Thursday night, rattling off five no-hit innings before Castellanos broke through with a clean single to right in the sixth. The St. Louis right-hander ended with nine strikeouts, two walks and just the lone hit relinquished in his seven frames against Chicago.

Overall, the Cubs scored three runs in the three games in St. Louis.

“I mean, their guy did pitch well, but we just have to be better offensively,” Maddon said. “That's really it in a nutshell. They got some runs tonight -- I get it -- but we've got to get better offensively. Hopefully by getting home, more familiar backdrop, I don't know.”

The biggest problem on the road overall for the Cubs has been the pitching, and that compounded matters again on Thursday.

Lester was charged with five runs in his five innings, though two came courtesy of a three-run homer that Derek Holland allowed to Matt Wieters in the sixth inning. The eight runs surrendered on the night upped Chicago’s team ERA to 4.73 on the road, compared to a 3.36 ERA at Wrigley Field this year.

“Do we believe in this team? Absolutely,” Hoyer said. “If we didn't believe in them, we wouldn't have been aggressive at the Deadline to add. But that said, I do think, yeah, there's frustration in figuring out why our road struggles are what they are.”

Don’t look now, but the Cubs finish the season on the road -- back in St. Louis.

“We as a group in this clubhouse have to figure it out and play better,” Lester said. “Regardless if [the front office] make moves or not, it's on us. It's not on them. Yeah, it's a nice boost, but we've got to go out there and play better.”