Baseball is Finally Back: MLB Rule Changes, All Pitching Matchups

It’s been 145 days since the last MLB game.

Today is opening day, and all 30 teams will play in 15 games. In the early afternoon, we will see Giants vs Yankees and Braves vs Nationals. Thirty of the top pitchers in the major leagues, including 21 All-Stars, eight Cy Young Award winners, and five pitchers making their debuts for new organizations, will take the mound (see full schedule below).

This season, there are five rule changes that promise to change the game in foreseeable and unforeseeable ways. Here they are in detail:

The Shift

The new rule

When a pitch is thrown, all four infielders are required to be on the infield dirt (or infield grass) with two feet on each side of second base. Players will be able to move as soon as the ball leaves the pitcher's hand. Originally in 1941, infielders who began the game on one side of the field would not be allowed to switch to the other side for the entirety of the game, but that will now be applied on an inning-by-inning basis unless there is a mid-inning substitution. In other words, a player who starts an inning at first or second base has to remain on that side of the field for the whole inning but can switch to short or third base the next inning. If there's an injury mid-inning, then the infield can be reset.

Pickoffs

The new rule

Pickoffs are one version of a "disengagement," which consists of any time the pitcher makes a pickoff attempt, fakes a pickoff, or simply steps off the rubber for any reason, as well as when the defense requests time. Pitchers are allowed two disengagements per plate appearance without penalty. The disengagement rule resets if a runner or runners advance a base within the same plate appearance.

Position Players Pitching

The new rule

Teams will be more limited in when they can pitch a position player. The previous rule allowed them to use one when up or down by six or more runs, but the sides are discussing a tweak in which the leading team would have to be up by as many as 10 or more while the trailing team would have to be down by eight or more in order to pitch a position player.

Bigger Bases

The new rule

The size of the bases will be increased from 15 inches to 18 inches.

Pitch Clock

The new rule

Pitchers will have 15 seconds to throw a pitch with empty bases and 20 seconds with a runner on base. Hitters must be in the batter's box with eight seconds on the pitch clock.