NEW YORK — Pitchers will be ejected and suspended for 10 games for using illegal foreign substances to doctor baseballs in a crackdown by Major League Baseball that will start Monday.

The commissioner’s office, responding to record strikeouts and a league batting average at a more than half-century low, said Tuesday that major and minor league umpires will start regular checks of all pitchers, even if opposing managers don’t request it.

While suspensions would be with pay, repeat offenders would receive progressive discipline, and teams and club employees would be subject to discipline for failure to comply.

“After an extensive process of repeated warnings without effect, gathering information from current and former players and others across the sport, two months of comprehensive data collection, listening to our fans and thoughtful deliberation, I have determined that new enforcement of foreign substances is needed to level the playing field,” baseball Commissioner Rob Manfred said in a statement.

“I understand there’s a history of foreign substances being used on the ball, but what we are seeing today is objectively far different, with much tackier substances being used more frequently than ever before. It has become clear that the use of foreign substance has generally morphed from trying to get a better grip on the ball into something else — an unfair competitive advantage that is creating a lack of action and an uneven playing field.”