WASHINGTON -- For two nights in a row the Nationals had played clean or "crisp" baseball, as manager Dave Martinez enjoyed calling it Friday afternoon, with his team fresh off back-to-back wins for the first time in a month. Another reason for optimism also arrived Friday with the return of electric shortstop Trea Turner from the injured list, putting the Nationals lineup at closer to full strength than they have been in weeks.

And yet, an ugly 14-6 shellacking at the hands of the Cubs on Friday night at Nationals Park served as a troubling reminder of the biggest issue facing the Nationals during this 2019 season. Washington's bullpen was at the center of yet another meltdown, surrendering nine runs in the final two frames to transform what was a one-run game entering the eighth inning into a 10-run deficit in the bottom of the ninth.

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"We were right there," Martinez said. "The game was a really good game, close game, and if the bullpen holds us, it's a different ballgame. Didn't do it tonight."

It wasn't just Friday night, the bullpen has been a problem for the Nationals all season. Four of the five relievers who pitched in this game -- Justin Miller, Joe Ross, Kyle Barraclough, Dan Jennings, Matt Grace -- all surrendered at least two runs. Cubs third baseman Kris Bryant homered in the seventh, eighth and ninth innings against Nationals relievers. Washington's bullpen ERA, already the worst in the Majors, somehow continued to increase.

After Friday's performance (three innings, five homers and 11 earned runs) Nationals relievers own a 6.82 ERA. They are currently carrying four relievers -- Grace, Jennings, Ross and Wander Suero -- with an ERA higher than 5.00. This relief core doesn't strike enough batters out (14th in NL in strikeout percentage), issues too many walks (seventh-highest walk rate in NL) and consistently gives up inherited runners (15th in NL in strand rate).

"It's obviously really frustrating," Barraclough said. "You get some guys that throw well and some guys that struggle, but outside of [closer Sean Doolittle], it's like everybody's had their ups and downs. So then you can't piece it together because you're trying to ride hot streaks, and then that guy stumbles and other guys step up. It's baseball and it's ups and downs, and we're still trying to figure it out."

This bullpen is a major reason why the Nationals' longest winning streak of the season remains two games. And why they have now lost eight times in 10 games with their best pitcher, Max Scherzer, on the mound. And why the Nationals find themselves with a better record than only the Marlins in the NL.

Despite these prolonged bullpen struggles, however, it appears this group of relievers is who the Nationals will have to count on if they want to save their season.

They do not have MLB-ready pitching prospects in the upper levels of the Minors and have already converted perhaps their two top young starters, Ross and Erick Fedde, to the bullpen -- although Fedde is likely headed to the rotation to replace the injured Aníbal Sánchez. And Friday night, the pitcher they signed to be their setup man, Trevor Rosenthal, was pitching in a rehab stint for Double-A Harrisburg, and it was not going well -- one hit, one walk and 11 strikes in 21 pitches, with two errant pitches reaching the backstop.

Miller is headed to the injured list with a rotator cuff strain, so the Nationals will call up another reliever Saturday to hopefully provide some new life to the bullpen. But major personnel changes do not appear to be on the horizon for the Nationals, who have to hope their bullpen suddenly has a turnaround more than two months into the season.

"This is the bullpen we have," Martinez said. "Yesterday they were really good, today they weren't. So they got to regroup."