Cotton (1-1) threw seven scoreless innings, walked three and struck out six, including the side in the fourth. The 25-year-old native of the Virgin Islands was tagged for five runs on eight hits and two walks over 4 1/3 frames, which matched the shortest outing of his brief career (Oct. 1 at Seattle). He likely got the call due to multiple lefties coming up in the ninth for Kansas City and Santiago Casilla having pitched the eighth.
Davis provided all the offense Oakland needed when he followed a leadoff single by Ryon Healy with his fourth homer of the year. The shot to right field on a 3-0 pitch from Ian Kennedy (0-2) barely scraped over the wall, but it gave Cotton the only help he needed against a punchless Kansas City lineup.
OUR PICK: The Royals are 5-1 in Kennedy's last six starts when he faces a team with a losing record and are 4-0 in his last four outings when their opponent allows five runs or more in its previous game. His only mistake was a 3-0 fat fastball to Davis, who took advantage of the wind blowing out to right to get it over the fence. The game ended with Brandon Moss striking out. Doolittle's save was his first since June 23, 2016. Royals RHP Peter Moylan pitched two ideal innings, extending his scoreless streak to seven.
A's third baseman Trevor Plouffe was charged with an error in the sixth.
Six people arrested after deadly St. Petersburg subway bombing
Investigators are apparently examining links between the arrested men and Monday's alleged bomber, 22-year-old Akbarzhon Jalilov. In the past two decades, Russian trains and planes have been frequent targets of attack, usually blamed on Islamic militants.
The Royals had seven total base runners and struck out 12 times. Pictures of him flashed on the massive, crown-shaped video board in center field and there was a moment of silence before a saxophonist began to play "Amazing Grace".
Ventura was preparing to report to spring training in Arizona on January 22 when he was killed on a risky section of road in the Dominican.
The pre-game ceremony concluded with Royals manager Ned Yost escorting Ventura's mother, Marisol Hernandez, and grandfather, Raul Hernandez, out to the mound to throw out the first pitch to Royals catcher Salvador Perez.