CHICAGO -- Cubs manager Joe Maddon knew going into Friday's game that his bullpen was running on fumes. Starter Kyle Hendricks also had that in mind when he took the mound. Chicago's recent string of games has included no off-days, some abbreviated starts and a handful of extra-inning contests.

"In the back of your head," Hendricks said, "yeah, you're thinking about it."

Hendricks fell one inning short of his goal of giving the Cubs seven, and the club's relief corps could not finish the job in a 6-5 loss to the Reds at Wrigley Field. There were some flares and bloops, but there was also a monstrous two-run homer in the ninth by Eugenio Suarez, who jumped and shouted up the first-base line as the North Side crowd unleashed a chorus of boos amid a storyline that refuses to die.

Throughout Chicago's quiet offseason, the need for bullpen help was a consistent theme. It persisted as a concern during Spring Training and then became an alarm-sounding issue in the first couple of weeks of the season. Overall, the Cubs' cast of relievers have steadied the ship in the past several weeks, but every run allowed creates a new wave of criticism crashing over the side.

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Cubs fans want Craig Kimbrel now (never mind that the free-agent closer would probably need a tuneup period before joining any team's big league bullpen). Maybe Chicago will pursue Kimbrel, but it would make more sense after next month's MLB Draft to remove compensation from the equation. It is more likely that the Cubs try to add an impact arm via trade, but the July 31 Trade Deadline is still off in the distance.

"I still think we're in a good spot," Cubs reliever Steve Cishek said. "As the fans ride the roller coaster, we do, too. There's ups and downs throughout a long season. We started off slow and then we rode a hot streak for a long time. It's going to happen again. We're going to be fine."

Will they be fine?

On the plus side, even with the three runs surrendered in the final three innings on Friday -- rendering three early homers and an inspired eighth-inning rally moot -- the Cubs rank fifth in the National League with a 3.98 bullpen ERA. Then again, a red flag exists in the 13 percent walk rate, which is last in the Senior Circuit. In the ninth, it was a leadoff walk by Cishek that set up Suarez's game-altering shot.

"You can't allow that leadoff walk to happen," Cishek said.

While the instant angst of social media will call for Cishek to never handle the ninth again, this is also where it is important to note that the sidearmer had not allowed a run since late April. He took the hill with a 0.00 ERA and a .353 opponents' OPS in his past 11 appearances, which included three multi-inning efforts. On the season, Cishek had a 2.35 ERA and just one homer yielded before Friday's setback against Cincinnati.

The problem on this afternoon was the domino effect that led to Cishek being in the game at all.

While Chicago's relievers do not rank near the top of the NL in terms of innings, the group had worked the second-most frames in the league over the previous nine games. During that stretch, which featured a pair of extra-inning games and some shorter starts, the Chicago 'pen had a collective ERA of 4.37 and an .826 OPS against.

On Friday, Maddon did not have Tyler Chatwood, Brandon Kintzler or Carl Edwards Jr. available. Before the game, James Norwood was summoned from Triple-A Iowa to offer a fresh arm. After the Cubs’ manager squeezed 1 2/3 innings out of Brad Brach and utilized lefty Mike Montgomery, Cishek made sense as the option to handle the ninth with Chicago clinging to a 5-4 lead.

There was an underlying problem, though.

"He probably didn't have a full tank," Maddon admitted. "Probably three-quarters maybe. So, the stuff wasn't as clean or crisp."

Told of Maddon's assessment, Cishek did not want to go down that road.

"I don't have a comment on that," said the reliever.

Maddon also noted that the Cubs are not alone in the need for more bullpen stability. Relief issues have hurt some other contenders, including the Dodgers (4.62 ERA), Twins (4.28), Brewers (4.31) and Braves (4.39), among others. Entering Friday, the MLB-wide bullpen ERA of 4.35 was the highest since 2000 (4.56).

“It's pretty much an industry-wide concern right now. It's not just here,” Maddon said.

The good news is that there is some help on the way.

No, there is still no sense of a real timeline for the return of injured closer Brandon Morrow (right elbow), who recently resumed playing light catch out at the Cubs' facility in Arizona. Reliever Pedro Strop, however, is slated to throw off a mound again Saturday and could be coming back from the injured list soon after his bout with a left hamstring issue. That would help solve part of the late-inning committee.

"When Stropy comes back, then all these guys get pushed back," Maddon said. "It just lengthens your bullpen."

Strop was asked recently what he thought about the idea of adding more external help for the bullpen.

"I haven't heard anything about it," Strop said. "Personally, I don't like to get involved in whatever is [front] office decisions. Whatever they do, we're going to accept it. And if they bring in some new guys, we're just going to incorporate it in our group and let them know how we have fun here."