Prominent U.S. sportsbooks are establishing a nationwide $200 betting limit on baseball wagers centered on individual pitches and prohibiting such bets from being included in parlays in an attempt to decrease the incentive for manipulation, Major League Baseball announced Monday.

MLB has been in discussions with its authorized sportsbook partners about potential changes to betting menus and limits since the summer, after unusual wagering was detected on individual pitches by Cleveland Guardians starter Luis Ortiz in a pair of June games.

On Sunday, federal prosecutors unsealed an indictment that charged Ortiz and Guardians closer Emmanuel Clase for their alleged roles in a gambling scheme centered on whether individual pitches would be balls or strikes as well as the over/under on the velocity of some pitches. According to the indictment, gamblers won approximately $450,000 on bets on individual pitches during the alleged scheme.

Ortiz appeared Monday in federal court in Boston and was granted his release on the condition he surrender his passport, restrict his travel to the Northeast U.S. and post a $500,000 bond, $50,000 of it secured.

MLB said reducing the amount bettors can win on such markets will disincentivize attempts at manipulation. Baseball has worked with the sportsbook industry over the past seven years to “uphold our most important priority: protecting the integrity of our games for the fans,” MLB commissioner Rob Manfred said.