Multiple Major League Baseball teams reportedly plan to ask umpires to check for foreign substances on opposing pitchers as the league begins to enforce the rule starting Monday.

Buster Olney of ESPN reported that "at least three teams intend to set aside" any existing informal agreement that managers won't ask umpires to check pitchers so their own pitchers aren't checked.

Instead, "if the managers of those teams receive information that seems suspicious—video capturing an opposing pitcher perhaps using foreign substances, or data about an unusual spike in spin rate—they will ask umpires to check opposing pitchers."

Major League Baseball announced Tuesday that it planned on having umpires strictly enforce rules against such substances that have long been ignored.

The announcement said there will be "regular checks of all pitchers regardless of whether an opposing club's manager makes a request," so the three teams that plan on doing so may not even need to if the umpires are already checking.

Pitchers will be suspended for 10 games with pay if they are caught.

"We've been telling our pitchers that if they have been using, they need to stop," a talent evaluator said, per Olney. "We are looking to level the playing field. The whole sport is looking to level the playing field. We have an expectation our guys will honor the rule. If we get an indication that there's someone pitching for the other team who might be doing something to gain a competitive advantage, yes, we will want our manager to challenge that."

Pitchers using such substances to help with their grip and improve their overall spin rate has been a major talking point this season.

Former Los Angeles Angels visiting clubhouse manager Brian Harkins told Stephanie Apstein and Alex Prewitt of Sports Illustrated he gave substances to multiple pitchers, including Gerrit Cole, Max Scherzer, Justin Verlander, Corey Kluber and Adam Wainwright.

The topic figures to remain a prevalent one throughout the season, especially as umpires start to check and enforce the rules.