But when Royals manager Ned Yost opted to bring in right-hander Birch Smith, McEwing let Palka hit.
Palka hit a three-run homer, part of his big performance as the White Sox beat Kansas City 8-0 Saturday in the first game of a doubleheader.
Palka had four hits and scored three times and Carson Fulmer allowed four singles over seven innings to lead Chicago.
"They didn't announce Trayce's name, so when they brought in another pitcher, they told me to come back out," Palka said. "Worked out pretty good. That's a pretty funny story."
Palka, who was hitless in his first eight at-bats since debuting Wednesday, was a triple shy of a cycle.
The White Sox are 5-0 against the Royals this season and 3-16 against other opponents. The Royals have been outscored 32-11 during a five-game losing streak and are a major league-worst 1-12 at home. They have lost 15 of their last 17.
Fulmer (2-1) left after 109 pitches, walked three and struck out three. In his past two starts, he has allowed seven hits and two runs over 13 innings.
Matt Davidson, who has seven home runs against the Royals this season, hit a double and two singles.
Palka, Tim Anderson and Leury Garcia, the White Sox 7-8-9 hitters, went a combined 8 for 13 and scored five runs. Yolmer Sanchez also drove in three runs with a bases-clearing double in the fourth inning.
McEwing managed in place of Rick Renteria, who attended his mother's funeral.
Trevor Oaks (0-1), who was the Royals' 26th man, gave up five runs on 12 hits over five innings in his major league debut.
"Obviously, a lot of excitement and adrenaline, but it didn't exactly go the way I wanted it to," Oaks said. "I got out of a couple of jams. I'm going to learn a lot from this. I think it's a good first start. I'm going to move forward and do the best I can to get back up here for sure."
"Making it to the big leagues, a lot of people kind of take that and they just give up after that, like they've accomplished that they've arrived. I think this is just a first step for me and hopefully a long career," he said.
The Royals loaded the bases in the first inning on walks to Salvador Perez and Jorge Soler sandwiched around Lucas Duda's single, but Jon Jay flied out to the right field warning track to end the threat.
"Jay hit the ball really good," Royals manager Ned Yost said. "I was hoping he would get enough of it to give us a nice little lead to work off of, but not quite enough."
Soler has walked in eight straight games, matching the longest streak this season in the majors.
Fulmer retired 18 of the final 22 hitters he faced.
"Jay barreled it up about as good as he could and put a really good swing on it," Fulmer said. "Luckily the wind was blowing in quite a bit to keep it down. I haven't really had to face too many guys with two outs, bases loaded."
The Royals recalled RHP Scott Barlow from Triple-A Omaha and optioned Stout, who threw 23 pitches in the first game, to the Storm Chasers between games. . The White Sox recalled RHP Dylan Covey from Triple-A Charlotte to start the second game. They optioned RHP Gregory Infante to Charlotte. . Reliever Juan Minaya was called up from Triple-A Charlotte to serve as the White Sox 26th man for the split doubleheader.
Royals RHP Clay Buchholz allowed one earned run on four hits over five innings in a no-decision in a start for Triple-A Omaha at Colorado Springs. The 33-year-old, who was two-time American League All-Star selection with Boston, is 1-0 with a 1.13 ERA in three minor league starts. He signed a minor league contract in late March with the Royals with an out clause if not added to the big league roster by Tuesday.
White Sox: LF Nicky Delmonico returned to the lineup after missing the previous two games with a stiff neck.
The Royals will start RHP Ian Kennedy in the series finale. Kennedy left his previous start after three innings with a bruised toe from a line drive. The White Sox have not yet announced their starter.