Shares of sports betting service DraftKings were down about 8% shortly after noon on Monday after the MLB postponed two upcoming series due to the Covid-19 pandemic.

Earlier Monday, Major League Baseball postponed the Miami Marlins three-game opener against the Baltimore Orioles and the Philadelphia Phillies’ series against the New York Yankees. The decision was made after more than a dozen members of the Miami Marlins tested positive for coronavirus, according to the AP.

DraftKings told CNBC that MLB was the most popular sport in its sports book this weekend. And, over the weekend, DraftKings had the second best day since the March shutdowns began, showing just how important baseball is for the company. DraftKings lets people bet on the PGA Tour, MLS, the WNBA, NASCAR, among other sports.

Mobile betting is currently only legal in 7 states, however, and last year at this time mobile betting was only legal in New Jersey.

DraftKings expected pent-up sports betting demand as teams returned to play. In May, CEO Jason Robins said the company had seen interest as people started to watch eports while leagues, including the MLB and NBA, were on pause due to the coronavirus outbreak.

“People are hungry for sports to come back,” Robins said in May. But, now that sports are beginning to return in limited capacity, there’s concern that they’ll be placed on pause again.

Still, DraftKings has fared well during the pandemic. Shares of the company are up 221.31% since the company went public in April.

CNBC’s Jessica Golden contributed to this report.

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