It will be just the third start of the season for the 2015 American League Cy Young Award winner, who signed a minor league contract with the Twins on June 22.
Keuchel (0-1, 9.45 ERA) was solid in his first start, a 5-3 victory over the Arizona Diamondbacks on Aug. 6 at Target Field. He allowed one run on eight hits over five innings.
However, Keuchel comes in off a 13-2 loss at the Philadelphia Phillies on Aug. 11 that saw him allow six runs on six hits in just 1 2/3 innings. It was just the third time in 259 career starts that he was unable to get out of the second inning.
"It's very frustrating," Keuchel told MLB.com. "I feel like I've made some quality pitches in my two starts here, so it's just one of those things where, like I said, you've got to tip your cap a little bit. I'm a little frustrated, but at the same time, there's nothing I can do at this point to re-correct."
Perhaps the 35-year-old Keuchel can get a little inspiration from another veteran player.
Andrew McCutchen, 36, homered and drove in five runs to help Pittsburgh even the series with a 7-4 victory on Saturday.
McCutchen, who won the National League MVP in 2013, moved past Dave Parker into ninth place for most RBIs in team history with 761.
"It speaks volumes, and I don't take it lightly," McCutchen said. "It's nice when I hear things like that. It lets me know what I've been doing. ... It's nice that I'm able to step up today and produce."
The three-run blast into the second deck in right-center field off reliever Jordan Balazovic was McCutchen's first homer since June 30 and the 298th of his career.
"It's really special," Pirates manager Derek Shelton said. "I think we know what 'Cutch' means to this franchise. He's passing some guys who were elite players."
Pittsburgh starter Mitch Keller won his first game since June 28 to improve to 10-8. Keller allowed two runs over six innings while striking out 12, including the side with the bases loaded in the sixth inning as the Pirates nursed a 3-2 lead.
"It was huge," Keller said of striking out Royce Lewis, Donovan Solano and Joey Gallo to end the threat. "It could have gone really south, really quick. It could have turned a great night into a terrible one. Couldn't be happier."
"We definitely missed some chances," Minnesota manager Rocco Baldelli said. "It felt like a game that we let slip away in some ways."
Shelton announced after the game that left-hander Ryan Borucki (1-0, 4.07) will make his second start of the season on Sunday.
Borucki is 0-1 with a 1.86 ERA in five career games (one start) against the Twins. He allowed one run on one hit in one inning of relief in Friday's 5-1 series opening loss.
—Field Level Media