Just did a whole bunch of reading. 10-4-5a has the phrase "or from being put in play" which is not included in any of the rules or references that allow for a delay warning.
By literal rule, I'm tending in this direction of not issuing the delay in conjunction with the player T for delay of game per 10-4-5a, though it seems that what the player did was more egregious than "reaching over the boundary line" to contact the ball in the thrower's hands. An anomaly, perhaps. I can see selling it either way. Glad it's rare.
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