In addition, the stakes will remain fairly pedestrian between the two National League Central also-rans.
Cincinnati (59-78) will be playing the final three games of 16 in a row within the division. The Reds are 4-9 so far in that stretch but got a boost from winning two of three against St. Louis over the weekend, including a 6-4, 10-inning win Sunday.
"This series we played better, and we got a W, we got a series (win)," Eugenio Suarez told Fox Sports Ohio after he hit a winning two-run homer, giving him 100 RBIs.
Even with a sweep of this series, the last-place Reds would be hard-pressed to catch the fourth-place Pirates in the division but can continue to build for the future.
"We're trying to turn the page from a terrible August and see if we can play better baseball in September and take that into the offseason and into spring training -- just get back to winning baseball," Cincinnati manager Jim Riggleman said.
"We want to win games. We don't care who the opposition is or whether it's against any of these three (previous) teams competing for playoff spots. We're not out there trying to spoil their hopes; we just want to win games for ourselves."
There won't be much the Reds could spoil for the Pirates anyway.
Their carrot would seem to be finishing above .500.
Pittsburgh (66-71) was 3-6 on a road trip against Milwaukee, St. Louis and Atlanta, and was 2-5 on a preceding homestand against Atlanta and the Chicago Cubs, making it five straight series against clubs holding a playoff spot.
The Pirates are coming off a 5-1 loss Sunday to the Braves.
Williams seemingly is vying for the title of Pirates ace, particularly with his performance since the All-Star break, going 4-2 with a 0.84 ERA in seven starts. Over his past eight starts, he has allowed four runs.
Wednesday, Williams pitched six scoreless innings and struck out a career-high eight in Pittsburgh's 2-0 win at St. Louis.
Before his strong stretch, over nine starts he had a 7.02 ERA and competed six innings three times.
"It's fight or flight, really. I didn't want that to define me this year," said Williams, who leads Pittsburgh's starters in ERA and with a 1.19 WHIP. "It was really taking that second half and making the most out of it, where I give our team the best chance to win every five days and execute my pitches and keep the guys in the ballgame."
Against Cincinnati, Williams is 2-1 with a 4.73 ERA in seven career appearances, four of them starts.
Harvey is 1-0 with a 3.18 ERA in his past four starts.
Wednesday against Milwaukee, he did not get a decision in a 13-12 extra-inning loss. Harvey struck out six and walked none in four innings but gave up five runs and 11 hits.
In eight career starts against Pittsburgh, he is 2-6 with a 6.12 ERA.