CHICAGO -- The Pirates’ pitching staff made history for all the wrong reasons this weekend at Wrigley Field.

The Cubs battered the Bucs’ rotation and bullpen for the third straight game on Sunday, handing Pittsburgh a 16-6 defeat to cap a historically rough three-game sweep. The Pirates were outscored 47-15, matching their modern-era record (since 1900) for most runs allowed in a three-game series.

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“You tip your cap to a club that did that, especially in a three-game series. When clubs are hot like that, you can’t make mistakes,” starter Trevor Williams said. “The mistakes that you do make get hit out of the park. But it’s something that we can hone in on and not let this drag us down for the next two weeks.”

The only other time since 1900 that the Pirates have surrendered 47 runs during a three-game set was June 23-25, 1950, against the Brooklyn Dodgers. This is also the first time since at least 1908 that they've given up 14 runs or more in three straight games.

According to the Elias Sports Bureau, the Cubs became just the fifth team in the modern era to score at least 14 runs in three straight games, joining the 1901 and ‘28 Pirates, 1930 Cubs and 1993 Tigers.

Broken records aside, the story on Sunday was essentially the same as it was on Friday and Saturday. The Pirates’ starter got hit hard and exited quickly, the bullpen couldn’t stop the bleeding and the Cubs kept getting on base, to the tune of a .496 OBP during the series.

In the series finale, Williams allowed seven runs on six hits, including two home runs by Kris Bryant, while recording only seven outs. The Pirates’ three starters -- Steven Brault, James Marvel and Williams -- combined to give up 24 runs on 23 hits and nine homers while working only nine innings against the Cubs this weekend.

“We’re going to take the off-day and kind of regroup and show up at the yard on Tuesday and dial in what we need to get better at,” Williams said. “It’s hard to find positive in a three-game series like this. However, we have to search for those and we have to glorify those and also be real with the mistakes that we’ve made and understand that changes need to be made.”

The Pirates’ middle-relief corps, mostly a mix of in-season waiver claims and prospects who have struggled to make the leap from Triple-A, combined to allow 23 runs on 26 hits in their 15 innings at Wrigley Field.

On Sunday, the Bucs broke their modern-era franchise record by allowing at least 10 runs for the 29th time this season. In roughly a third of the Pirates’ 85 losses this season, Pittsburgh’s opponent has finished with a double-digit run total.

“Nobody is looking for sympathy out there. Nobody is looking for pity,” manager Clint Hurdle said. “We have to fight and keep playing. It’s what they’ve done most of their life. Just because you’re doing it here doesn’t make it any more dramatic. You just need to figure it out and play better, the best of our abilities with the men that we send out there and the pitchers that we send out there.”

The wins were far more meaningful for the postseason-contending Cubs than the losses were for the Pirates, who were officially eliminated on Saturday, but the results were no less real, and the long-term ramifications no less concerning. Barring a dramatic and unexpected change of direction in the offseason, most of this roster will return next year.

That might be good news for the lineup, which bounced back from a one-run performance on Saturday to rack up 14 hits in the series finale even without Starling Marte and Josh Bell. Bryan Reynolds remained a bright spot and made one positive bit of history, breaking Paul Waner’s franchise record for most doubles by a rookie.

But the series was a giant red flag for the pitching staff, which owns a 5.23 ERA that ranks 27th in the Majors, especially considering pitching was supposed to be the strength of this team.

Chris Archer will be back next season, and perhaps Williams will return to form after being derailed by a midseason injury this year. Maybe top prospect Mitch Keller will take a step forward. But the Pirates will be without Jameson Taillon, and general manager Neal Huntington downplayed the idea that they’ll be able to acquire someone with his front-line potential.

“Every team would love to add a top-of-the-rotation guy. It’s not that we’re not looking for that,” Huntington said. “There’s [the] reality of market size, trade acquisition cost and the ability to take some of our own guys and push them to those levels that either they’ve been or we think they can get to.”

That kind of development is essentially what the Pirates are banking on heading into next season. They believe their pitchers are better than they’ve performed this season or that they have the ability to improve on what they’ve done this year.

“That’s how we get those guys back,” Huntington said. “We continue to help them become the pitchers they’ve capable of being, whether that’s getting them back to an established level or helping them to take that next step.”

If they don’t, the Pirates could experience more long weekends like this one.