For the first time, an active Major League Baseball player will endorse a bookmaker in the United States.

MaximBet and Colorado Rockies outfielder Charlie Blackmon have reached a partnership that will have the four-time All-Star appearing as a brand ambassador in marketing campaigns, promotions and social media content and at fan events for the online sportsbook.

Blackmon, per MLB policy, is not allowed to promote betting on baseball specifically but can endorse the sportsbook in general.

He is the first player to capitalize on opportunities in the sports betting space that were included in baseball's new collective bargaining agreement. Marketing and sponsorship deals with sportsbooks were restricted to league and team entities but prohibited for players and coaches prior to the CBA that was put in place this offseason. Players, coaches and MLB personnel remain prohibited from betting on baseball.

The deal between Blackmon and MaximBet is the latest example of MLB's embrace of the expanding legal sports betting market in the United States. Legal bookmakers are operating in 30 states and the District of Columbia, and multiple MLB ballparks are putting in physical sportsbook spaces.

In a recent interview on SportsCenter, MLB commissioner Rob Manfred touted the future of in-game betting on baseball.

"We see it primarily as a form of increasing fan engagement. It's an additional way for our fans to interact with the game," Manfred said. "I do think in-game betting is going to be a significant component. I think if you talk to people who are experts in the field that they don't see outcome betting as a major growth area. It is in fact in-game betting, so-called prop betting, that is going to be the growth area. And most of that betting is going to take place on mobile devices."

MaximBet, an offshoot of the lifestyle brand Maxim, is a newer online sportsbook in the U.S. and currently operates only in Colorado. It has announced plans to expand into Iowa and Indiana.

"As I learned more about MaximBet, I knew this absolutely was the right brand for me," Blackmon said in a release announcing the partnership. "MaximBet has really attached itself to the local Colorado community, and I cannot wait to have some fun with MaximBet and surprising fans with incredible 'money can't buy' experiences all season."