Ball Thrown Out-of-Play from Outfield

 
With a runner on 1st base (R1) stealing on the pitch, the batter (B1) hits a single to center field. The speedy R1 rounds 2nd base and is more than half way to 3rd, but he changes his mind and heads back toward 2nd base.
 
The centerfielder's throw towards third base is wild, gets by the 3rd baseman, and goes out of play. When the centerfielder released the ball that went out of play, R1 was heading back toward second base but B1 had not yet reached 1st base. When the ball went out of play, B1 had touched and rounded 1st base. 
 
Where do the umpire place R1 and B1?
 
Call
When a throw from an outfielder goes out of play, it is a two base award, determined from the base that the runners occupied at the time of the throw (NF 8-2). It does not matter if the runner was close to the next base or which direction the runner was heading.
 
In the situation below, at the time that the centerfielder released his throw, R1 was between 2nd and 3rd base. B1 had not yet got to 1st base. R1 is awarded home while B1 is awarded 2nd base.