With no outs and the bases loaded, the batter hits a fair ground ball to the third baseman. The third baseman fields the grounder and throws home in an attempt to force out R3 at home.  However, the throw home hits R3 -- while R3 is running with both feet completely in fair territory. R3 scores and all other runners are safe. 

 

The defensive coach reminds the umpire that this is a "textbook" case of a runner's lane infraction? What do the umpires do now?