Guthrie will try to rebound from a rare defeat in Monday night's series opener against the Houston Astros.
The Royals (20-20) were a season-best seven games above the break-even point and one-half game off the AL Central lead May 5, but they've since dropped 10 of 13. Lack of offense has been the main culprit, as Kansas City has scored three of fewer runs nine times during that stretch.
The Royals plated five total runs in three straight losses at Oakland over the weekend, with third baseman Mike Moustakas going 0 for 11 and shortstop Alcides Escobar's 0-for-12 stretch ending with a single in a 4-2 defeat Sunday.
"We definitely need to score runs the way the pitching has been - it's been amazing," center fielder Lorenzo Cain told MLB's official website. "So we definitely got to do our part as an offense and start getting it done."
Kansas City's starters have a 3.72 ERA, and Guthrie (5-1, 2.82 ERA) has played a big part in that. The right-hander went a team-record 18 consecutive starts without a defeat before surrendering season highs of five runs and 11 hits in seven innings of a 6-2 loss to the Los Angeles Angels on Tuesday.
The defeat was Guthrie's first since Aug. 3.
"Now we just start a new streak for him," manager Ned Yost told the Royals' official website.
To do so, Guthrie may need to do a better job keeping the ball in the park - something he's struggled with throughout his career. He gave up a career-high four home runs Tuesday, increasing his season total to 11 - among the most in the major leagues.
The Astros (12-32) are 12th in the AL with 42 homers, but 24 of those have come at home, including six in their last three games there.
Houston, loser of four straight against visiting teams, opens an eight-game homestand after splitting the last four on a 2-4 trip.
"We're playing a lot better," manager Bo Porter told the Astros' official website following a 1-0 loss to Pittsburgh on Sunday.
The Astros, who dropped two of three in Kansas City's last visit June 18-20, will give the ball to Dallas Keuchel (0-1, 4.82) in the series opener. The left-hander will get his third start since making his first six appearances this season out of the bullpen.
Keuchel didn't get a decision in either start, giving up four earned runs in 5 2-3 innings of a 7-5 win at Detroit on Wednesday.
Keuchel has never faced the Royals.
Kansas City's Alex Gordon is batting .500 during a seven-game hitting streak after matching his career high with four hits Sunday.
Kansas City, winner of nine of 13 against the Astros, last dropped four straight on the road during a six-game skid Sept. 13-28.