Two outs on one ball
Runner on first, ground ball to the infield. You can get TWO outs if you go to second first.
The rule: Runner on first, less than two outs, routine grounder: second base first, then first.
The setup
Runner on first. Grounder to you.
Both the runner and the batter HAVE to run. That means two bases with touch-the-base outs waiting: second and first.
Why second first
The runner on first has the shortest run.
They only have 90 feet to second, so that out disappears fastest. Grab it first. The batter has a longer run to first — there's still time to throw across for out number two.
What you lose
Go to first first, and you get one.
Out at first — but the runner strolls into second. Now they're in scoring position and nobody is forced anymore. One out when two were sitting there.
When it's not there
Slow roller? Take the sure out.
If you had to charge a dribbler, the runner is already at second. Don't chase it — throw to first and take the one out you know you can get.
You make the call.
Runner on first, nobody out. Sharp grounder right at you at short. Where is the play?