A person familiar with Blackmon’s situation confirmed the test result to The Associated Press on condition of anonymity because there was no official announcement.
The Denver Post first reported Blackmon’s condition, saying Tuesday that three Rockies players had tested positive.
Blackmon is a four-time All-Star slugger who hit .314 with 32 home runs and 86 RBIs last season. He turns 34 on July 1, the day players are set to begin reporting for the resumption of spring training.
Baseball Commissioner Rob Manfred imposed a 60-game season Tuesday night after failed financial negotiations between owners and players. The season that’s been delayed by the pandemic will begin either July 23 or 24.
The Philadelphia Phillies have said seven players have tested positive for the virus without identifying any of them. Several other teams have said they also have players who have tested positive.
The Post reported Blackmon tested positive last week after workouts at Coors Field in Denver. The newspaper said the Rockies then closed the ballpark, following MLB protocol.
Many players around the majors have been working in recent weeks at either their home ballparks or their team’s complexes in Florida or Arizona. MLB closed all spring camp sites last Friday because of virus concerns.
Blackmon has been an All-Star the last three seasons. He is a career .304 hitter in nine years.