Major League Baseball is testing limits on outfield positioning in this year's Arizona Fall League. The aim is to produce more extra-base hits. Yahoo Sports' Ian Casselberry reported that under the rule, outfielders have to play "straight up." That means they can't shift in one direction or the other based on the hitter's tendencies.

The Associated Press, via Sportsnet, called it the league's newest experiment in its long-running quest to juice the game's sluggish offence. It said the restriction applies to every at-bat. ESPN added a detail on enforcement: players consult a videoboard to see whether they are properly positioned.

The outlets differ in emphasis. Sportsnet's AP piece frames the test as being in the minors generally, while Yahoo and ESPN place it specifically in the Arizona Fall League. The feed summaries we have don't say how a violation is penalized, how the "straight up" alignment is defined, or whether the rule covers infielders. Those details may be in the full stories, but we haven't seen them. The Reddit post on r/baseball only links to the ESPN story and adds nothing.

The summaries also give no timeline for a possible move to the majors, and no data from the test so far. We haven't checked our archive for league-wide extra-base hit numbers, and nothing here shows how much the rule might change them. What to watch is whether MLB releases results from the Fall League and whether it names any plan to widen the test.