Teach learners to identify who hindered whom before choosing a penalty. This complete lesson separates two commonly confused calls through a visual decision path and eight original game situations.
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By the end of the lesson, learners should be able to:
Do not begin with whether the collision looked serious. Begin with the ball, the protected action, and which side prevented the other from completing it.
A fielder who is not in possession of the ball and is not fielding a batted ball impedes a runner’s progress.
Usual resultThe umpire protects the runner to the base or bases the runner would probably have reached. Whether play stops immediately depends on whether a play is being made on that runner.
An offensive player hinders or confuses a fielder attempting to make a play. A fielder fielding a batted ball has priority over a runner.
Usual resultThe offending runner is out, the ball is dead, and other runners return unless another rule provides a different placement or additional out.
A fielder fielding a batted ball has special priority; a thrown ball does not give the same blanket protection.
Offence hindering defence points toward interference. Defence hindering a runner points toward obstruction.
When several fielders converge, the umpire protects only the one entitled to make the play.
Intent matters in some thrown-ball and post-deflection cases, but a runner can interfere with a batted-ball fielder unintentionally.
That decides whether obstruction stops play now or is resolved after the action ends.
Ask: “A runner and fielder collide. Who is at fault?” Record answers, then explain that the rule cannot be decided until the group knows what the ball and fielder were doing.
Use the two cards above. Have learners point from the side doing the hindering toward the side being hindered, then name the possible call.
Model two fielders approaching one ground ball. Protect one. Then contrast obstruction during a rundown with obstruction while the ball is elsewhere.
Learners complete the eight situations. Require a ruling, the entitled player, and one decisive fact.
Sort the situations into interference, obstruction, and neither. Ask which examples prove that contact and intent are unreliable shortcuts.
For each play, name the ruling and the decisive fact. These situations use the 2026 MLB Official Baseball Rules.
R1 runs from first toward second and collides with the shortstop while the shortstop is moving into position to field a ground ball. R1 did not mean to cause contact.
What is the ruling?
A slow ground ball draws the shortstop and pitcher together. The umpire judges that the shortstop is entitled to field it. R1 avoids the shortstop but bumps the pitcher, who has crossed the running path.
Is R1 automatically guilty of interference?
The first baseman has no ball and is not fielding the batted ball. Standing in the batter-runner’s path, the fielder makes the batter-runner slow and detour before reaching first.
What should the umpire call, and when does play stop?
R1 is rounding second on a hit to the outfield. The shortstop, who has no ball and is not fielding the batted ball, bumps R1 off stride. No throw is being made toward R1.
Does play stop immediately, and how is the runner protected?
R2 is trapped between second and third. While a throw is coming toward third, the third baseman—still without the ball—blocks R2’s path and causes R2 to stop.
What is the call and base award?
R1 runs normally toward second. A fielder’s throw accidentally strikes R1 in the back. R1 did not look back, wave an arm, or alter course to meet the ball.
Is this automatically interference?
Seeing a throw headed toward second, R1 deliberately knocks it away with a hand to prevent the defence from completing a play.
What is the ruling?
A fair ground ball glances off the third baseman, then strikes R2 running behind the fielder. No other infielder has a chance to make an out. R2 did not deliberately touch the ball.
Is R2 out for being hit?
Credit the ruling only when the explanation identifies the protected action and the player who hindered it.
A runner must avoid a fielder attempting to field a batted ball. Intent is not required in this situation. Other runners return unless another rule sets a different placement. Rules: 5.09(b)(3) and 6.01(a)(10).
Only one fielder is entitled to protection on a batted ball, and the umpire selected the shortstop. Contact with the other fielder does not make R1 out. If the pitcher’s position impeded R1, the pitcher is instead subject to an obstruction call; an intentional act by R1 could still change the ruling. Rules: 6.01(a)(10) Comment and 6.01(h).
The fielder without the ball impeded the batter-runner before first base. The batter-runner is awarded at least first, with other runners placed to nullify the obstruction. Rule: 6.01(h)(1).
No play was being made on R1. The umpire signals obstruction, lets the action finish, then awards the base or bases R1 would probably have reached without the bump. Rule: 6.01(h)(2).
A play was being made on the obstructed runner. R2 receives at least one base beyond the last base legally touched before the obstruction, so R2 is awarded third. Rule: 6.01(h)(1).
A runner is not automatically out when a thrown ball accidentally strikes them during normal running. Deliberately interfering with a thrown ball would change the ruling. The ball remains live absent another violation. Rule: 6.01(a)(10).
R1 intentionally interfered with a thrown ball. Other runners return to the last bases legally touched at the time of interference unless another provision applies. Rules: 5.09(b)(3) and 6.01(a)(10).
The fair ball had passed or deflected from an infielder and no other infielder had a play. The ball remains live. A deliberate kick or touch by R2 would instead be interference. Rules: 5.09(b)(7) and 6.01(a)(11).
This material paraphrases the rules for teaching; it does not replace the official wording.