Infield Fly - Untouched

[brumey1107]

I'm looking for clarification/confirmation on the Infield Fly Rule.

In review of the OBR definition of terms with regards to the infield fly rule it states in part "The ball is alive and runners may advance at the risk of the ball being caught, or retouch and advance after the ball is touched, the same as on any fly ball."

My question is, Does the phrase "after the ball is touched" apply even if ball drops to the ground untouched and stays in fair territory?

Example: R1 and R2, no outs. BR hits high pop fly in infield. Infield Fly is called. F6 calls for the catch, but looses the ball in the sun and it drops untouched in fair territory to the ground and remains in fair territory.

In this scenario the runners need to retouch their bases, correct?

Thanks in advance for your help.