James Wood, of the Washington Nationals, reacts after hitting a double against the Cincinnati Reds.

The Inning Continues

With a runner or runners on base, the pitch timer counts down from 18 seconds, and all of the other logic regarding said timer remains the same as it is when the bases are empty: the next hitter must be ready with at least 8 seconds left, the pitcher must start their motion before the timer runs out. The clock generally starts when the pitcher receives a new ball.

Meanwhile, the defense will usually make adjustments to their positioning. The most drastic of these is that if there is a runner on first, the first baseman will usually take up a position directly at first base, reaching towards the pitcher. This is called "holding on the runner," and it's all to set up a play called the “pick off,” where the pitcher attempts to surprise the runner by throwing the ball to first base, whereupon the first baseman tries to tag the runner before they get back safely. If the runner is tagged while still off the base, they are out. More on all that in a little bit.