Scherzer was terrific in beating the Chicago White Sox on Friday, as he allowed just two hits - a pair of solo home runs - in eight innings to improve to 11-10 on the year to go along with a 3.54 earned run average.
"I made a couple mistakes, but I made a lot of good pitches tonight," Scherzer said after that game.
Scherzer lost to the Royals the last time he faced them and is 1-2 in four starts in this series with a 3.68 ERA.
He will be opposed tonight by righty Kyle Davies, who is 8-10 with a 5.08 ERA. Davies lost for the third time in his last five starts on Friday against Cleveland, which reached him for five runs and eight hits in five innings.
Davies beat the Tigers on August 24, but is just 3-7 lifetime against them with a 5.64 ERA in 11 starts.
Kansas City evened this series at a game apiece on Tuesday, as Mike Aviles had three hits and drove in three runs and Jarrod Dyson added three hits, three runs scored and a run batted in, helping the Royals to a 9-6 win.
Billy Butler chipped in three hits, a run and an RBI for the Royals, who have taken two of their last three games.
Chen (11-7) allowed three runs on four hits with a walk and one strikeout over six frames to win his third straight decision for the Royals, who have split eight games at Comerica Park.
Armando Galarraga (4-7) suffered the loss after allowing five runs on nine hits and five walks while fanning four over 5 1/3 innings for the Tigers, who had a four-game win streak halted.
"We had a lead and let it get away, and we can't do that and expect to win with those mistakes," said Detroit manager Jim Leyland.
The Tigers have won nine of 17 over the Royals this year.