First Base obstruction

Question
In todays game 17U, the batter popped up to the first basemen. First baseman was waiting for the pop up right in the base path  on the line. The runner ran into the first baseman on his way to 1st. The first baseman dropped the ball and the runner was called out at first. What is a runner supposed to do in that case. wait and let the 1st baseman catch, drop it and then run through?

Answer
The baserunner must allow the fielder to make a play on the ball, even if it means leaving the baseline. Same type of situation if a runner was going from 2nd to 3rd base, and a ground ball is hit to the shortstop. The baserunner must avoid the ball -- otherwise, it can be called obstruction, even if the runner doesn't touch the ball.