Baseball’s line between allowable, illegal substances remains fuzzy

For years, pitchers have used substances to make sure they get good grip on the ball. But as things such as spin rate have become easier to track, many of them are seeing the appeal of going beyond grip and are using substances to increase their spin.

They might have gone too far. Entering play Sunday, the major-league batting average was .238, the lowest since 1968.

As a result, Major League Baseball is planning to crack down on the use of substances that do more than enhance grip. But whether there’s a clear line between what’s allowed and what’s not isn’t yet clear.

‘‘I don’t think there really is, to be honest with you,’’ Cubs right-hander Kyle Hendricks said. ‘‘I don’t mess around with the stuff, so I don’t know as much about it as some other people. I would say that is the sticky situation of the whole thing, no pun intended. But they don’t know where the line should really be drawn.’’

That always has been a gray area, and the policy in baseball for years has been for the opposing manager to call out when the other team’s pitcher is using something illegal on the mound. The problem with that is no manager is going to call out another team’s pitcher if he knows guys on his team are doing it, too.

That is, until Cardinals reliever Giovanny Gallegos had his hat confiscated May 26 and manager Mike Shildt voiced his frustration with a situation that had been brewing for some time.

‘‘I think it was bound to come out, regardless,’’ Hendricks said. ‘‘As far as I know, from the start of the year, [MLB has] been taking baseballs and stuff like that, so I think they just needed a period to gather their info and see what is really going on and how bad is this or what is the problem. And now they’ve gotten enough data, I think, where they realize something needs to be done about it.’’

How new rules would be enforced still is taking shape. Hendricks said he has heard it might be checks in the bullpen, clubhouse or dugout between innings. Even if it involves in-game mound visits, the main concern for pitchers is that they know what to expect.

‘‘As long as the rules were out there on what it was supposed to be and this is what’s going to happen and we know what to expect,’’ Hendricks said. ‘‘If we’re in the dark about it and things are just being thrown at us, that’s different.’’

Not much Chicago spin

Cubs pitchers rank near the bottom of the majors in average spin rate and velocity, but that’s of little concern to manager David Ross.

‘‘I think we try to get people out,’’ he said. ‘‘I don’t correlate spin rate with outs. . . . Our guys get outs. I don’t care how hard they throw or what their spin rate is; I like outs.’’

Javy reinjures thumb

Shortstop Javy Baez was a late scratch from the starting lineup Sunday. He aggravated his right thumb, likely by diving for a ball Saturday. Issues with the thumb kept Baez out of all three games last week against the Padres in San Diego.