The Orioles optioned Mayo to Triple-A Norfolk on Thursday.
Mayo picked up his first major-league hit in Wednesday's win over the Nationals, but the young infielder went just 1-for-17 with 10 strikeouts in his first stint in the big leagues and had fallen behind Ramon Urias on the depth chart at third base. The 22-year-old's dynasty league outlook remains unchanged by the demotion, but Mayo shouldn't be counted on to deliver much value in redraft leagues the rest of the way.