Suwinski turned on a slider from Derek Law (2-1), sending it to right field. Fellow rookie Oneil Cruz, who opened the inning with his third of four straight singles, and Miguel Andujar scored to put Pittsburgh ahead 4-2.
''He continues to have good at-bats in this ballpark,'' Pirates manager Derek Shelton said of Suwinski. ''I think it's a really good thing we play 81 games here because he really likes hitting here. Good swings tonight. The double to put us ahead 4-2, that's a big hit driving through. He continues to have good at-bats. He continues to get better.''
Law hit Ke'Bryan Hayes with a pitch and walked Cal Mitchell before being replaced. Kevin Newman dropped an RBI single into right off Joel Kuhnel. Hayes scored on a sacrifice fly.
The last-place Pirates (57-97), who have won their past five against the Reds, must win at least six of their final eight games to avoid reaching 100 losses for the 10th time. Cincinnati has dropped four of five.
Yohan Ramirez (1-1) pitched the seventh and eighth for Pittsburgh, allowing two hits.
Cruz scored on a sacrifice fly by Andujar, extending the lead to 7-2 in the eighth. An RBI single from Hayes pushed it to 8-2 before a two-out homer by Aristides Aquino cut it to 8-3 in the ninth.
TJ Friedl gave Cincinnati a 2-0 lead in the third by driving a fastball from Roansy Contreras 412 feet out of PNC Park, clearing the Clemente Wall in right. The solo shot, Friedl's eighth of the season, came before a rain delay halted play for 38 minutes after the top of the fourth.
Contreras didn't come back out for the fifth, having allowed two runs on two hits in four innings.
''I think it's late in the year for a kid that hasn't pitched this late in the year,'' Shelton said. ''He doesn't pitch in cold weather a lot, so I think it's a combination of two things. It's like we talked about earlier in the year when we sent him out - we wanted him to finish the year, we wanted him to pitch. We knew we were going to have to monitor his innings.
''Ro is a big part of what we're doing now and a big part of what we're doing in the future. The fact that we knew it was going to be 45 minutes, minimum, there's no reason to send him back out there.''
Contreras said he didn't have a problem with being pulled.
''I felt pretty good,'' Contreras said. ''But I understood that it was part of the process with the rain delay, not going back out.''
Chase Anderson gave up two hits through the first four innings for the Reds before being pulled after a leadoff single by Kevin Newman in the fifth. He permitted one run and four hits with five strikeouts.
A pair of Reds errors helped the Pirates tie it following Anderson's exit.
Reiver Sanmartin came in to walk Zack Collins before allowing a bloop single from Cruz that dropped into shallow left, resulting in Friedl tossing it past third base. Newman broke for home as the ball trickled down the line, where catcher Chuckie Robinson gathered it, and won the race to the plate.
''It's fun to watch Cruz, you know?'' said Andujar, who was 1 for 3 in his Pirates debut after being claimed off waivers Sunday from the New York Yankees. ''I know him because he's from the Dominican. He's good guy, good dude, good player.''
Bryan Reynolds then grounded to second for what could have been an inning-ending double play. Instead, shortstop Jose Barrero took the exchange and sent the throw to first into the Cincinnati dugout, bringing in Collins.
Jonathan India doubled with one out in the first and scored for the Reds on a sacrifice fly.
Pirates: C Jose Godoy was selected from Triple-A Indianapolis. . INF Michael Chavis and OF Greg Allen were designated for assignment.
RHP Hunter Greene (4-13, 4.91 ERA) pitches for the Reds on Tuesday opposite Pirates RHP Mitch Keller (5-12, 3.99).
More AP MLB: https://apnews.com/hub/MLB and https://twitter.com/AP-Sports
Copyright 2022 STATS LLC and Associated Press. Any commercial use or distribution without the express written consent of STATS LLC and Associated Press is strictly prohibited.