Paul Skenes and Nick Lodolo had combined for 18 strikeouts through four-plus innings when the least likely suspect helped the Pittsburgh Pirates break the game wide open against the Cincinnati Reds.

After a ground-rule double in the fourth — his first extra-base hit in 17 games for the Pirates — Bryan De La Cruz added a bases-clearing double in a six-run fifth.

It provided all of the cushion necessary for Skenes, who delivered a dominant outing in six scoreless innings as the Pirates pounded the Reds, 7-0, on Thursday night before 16,635 at PNC Park.

It was the ninth shutout of the season for the Pirates (60-67), who were coming off a 1-0 loss at the Texas Rangers on Wednesday.

De La Cruz went 3 for 4 with three RBIs for his fourth three-hit game of the season and his best performance since being acquired from the Miami Marlins at the July 30 trade deadline. De La Cruz admitted he’d been pressing since he joined the Pirates.

“Yeah, I tried to do too much because when you get traded and you hit 18 home runs, that’s a little bit of pressure because they traded for a guy that they know that can hit home runs,” De La Cruz said through translator Stephen Morales. “I was trying a little bit too hard at the beginning.”

Pitching on five days of rest after stopping the Pirates’ 10-game losing streak against the Seattle Mariners on Aug. 16, Skenes recorded nine strikeouts against two hits and one walk.

It marked the fifth time in 17 career starts that the 6-foot-6, 260-pound rookie right-hander had nine or more strikeouts. Skenes relied on his four-seam fastball, which drew 11 called strikes and three whiffs.

“One of those things where the command of it was there, so we had to lean on it a little bit more,” Skenes said. “Just worked out well.”

Where Skenes (8-2) threw 53 of his 87 pitches for strikes before being pulled with a seven-run lead, Lodolo (9-6) didn’t allow a hit until De La Cruz doubled in the fourth but finished with five earned runs on two hits and three walks with nine strikeouts in 4 2/3 innings.

The pitchers were working with a generous strike zone from home-plate umpire Larry Vanover, which led to the early high strikeout totals and caused the Pirates to get creative with both their baserunning and defending the bases.

That started in the first inning, when Elly De La Cruz drew a one-out walk. With 60 stolen bases this season, the Pirates were wary of the Reds shortstop’s speed, so Skenes wasn’t about to let him get a lead. After being called safe on Skenes’ pickoff throw to first baseman Connor Joe, the Pirates challenged the call and it was overturned upon review.

That proved fortuitous, as Spencer Steer followed with a single to left field that would have put Elly De La Cruz in scoring position. Skenes got TJ Friedl to chase a changeup for a strikeout to end the frame.

Skenes was humming in the second inning, touching triple digits on his four-seam fastball and getting Amed Rosario, Santiago Espinal and Dominic Smith all looking at called third strikes on 99-mph heaters.

Skenes started the third by striking out his fifth consecutive batter, getting Noelvi Marte swinging at a splinker below the strike zone. He then went into ground-ball mode, which caused the crowd to gasp when Skenes lost his footing covering first base on an Elly De La Cruz groundout, slipping and falling on his backside.

After being tended to by assistant trainer Tony Leo, Skenes stayed in the game and got Spencer Steer to ground out to third before getting Friedl to chase a 98-mph fastball outside for his sixth strikeout.

Problem was, Lodolo was shoving, too. The Reds lefty recorded four consecutive strikeouts before Bryan De La Cruz broke up his no-hitter in the fourth with a jam-shot ground-rule double down the right-field line for his first extra-base hit with the Pirates since being acquired. Lodolo, however, responded by striking out Oneil Cruz to end the inning.

Lodolo finally got into trouble in the fifth, as the Pirates drew two walks, had two hit batsmen, three hits and scored six runs while batting through the order.

After walking Jared Triolo and Michael A. Taylor, he hit Isiah Kiner-Falefa with a pitch to load the bases with two outs. Then, instead of getting an inning-ending play, the Reds allowed the Pirates to score a run thanks to a baserunning play by Kiner-Falefa.

Bryan Reynolds hit a sharp grounder up the middle, only for Elly De La Cruz to scoop it and flip a backhand to second baseman Santiago Espinal. Kiner-Falefa ran through the bag, allowing Triolo to score for a 1-0 lead before getting into a rundown. Taylor took a few steps off third, giving the Reds pause and Kiner-Falefa enough time to get back to the base.

“Once I got past there, I was in no-man’s land. I didn’t know what to do,” Kiner-Falefa said. “I was able to get back, and we were able to keep the rally going, and it ended up being huge.”

Shelton called it an “unbelievable baseball play, unbelievable IQ play” by Kiner-Falefa, noting that first-base coach Tarrik Brock has wanted to run the play for years.

“It could not have been executed any better, and then the awareness that once he ran through it and was safe to continue to go because now you get a defense in no-man’s land,” Shelton said. “I think it stunned everybody, and he was able to get back. … That changes the whole dynamic of the inning. Lodolo’s cruising, we get the one run and all of a sudden we get the hit by pitch and it continues to roll.”

The Pirates added to their advantage when Lodolo hit Joey Bart with a pitch, scoring Taylor to make it 2-0. Then Bryan De La Cruz cleared the bases with a double to right-center off Reds reliever Jakob Junis to stretch the lead to 5-0. Oneil Cruz followed with a single up the middle to drive in De La Cruz to give the Pirates a 6-0 lead.

“The second one was the big one,” Shelton said of De La Cruz. “The one to clear the bases, that was a big hit.”

Yasmani Grandal hit his sixth home run, a 394-foot solo shot to right-center, in the sixth inning to make it 7-0. Ben Heller pitched a scoreless seventh and eighth and Hunter Stratton the ninth to finish the shutout.

The Pirates can trace it back to their fifth inning against Lodolo.

“He was getting a lot of help back there, though,” Kiner-Falefa said. “That was a tough night for both offenses. The way things were going, we had a lot of strikeouts. When things weren’t going our way, we had to find a way to scratch some runs. We were able to break it open.”

Kevin Gorman is a TribLive reporter covering the Pirates. A Baldwin native and Penn State graduate, he joined the Trib in 1999 and has covered high school sports, Pitt football and basketball and was a sports columnist for 10 years. He can be reached at kgorman@triblive.com.