I was the AR in a game yesterday with a similar situation to the game referenced above. The difference was that the player in the offside position broke toward the goal and ran ahead of the ball until he pulled up in front of the goal. When the ball was passed to him it had just brought him into an onside position. I raised the flag and and placed the kick where he was first offside. I got vehement protests from the sideline (as I was the bench side AR) and the debate raged on after the game, with experienced knowledgeable people. Was this the right decision or was he eligible to receive the ball as soon as it passed him? Note:this whole event took about 3 seconds.

Answer (April 29, 2014):
If the player had returned (or been returned by circumstances) to an onside position BEFORE his teammate played the ball to him and had not, as Navas had not, attracted any attention from his opponents or otherwise interfered with play or with an opponent, then he should not have called offside. Being in an offside position is NOT an infringement of the Laws, so the player should not be punished for something that occurred under the circumstances you describe.

For the benefit of others, I append here the answer of June 20, 2012:

Navas’s goal was legally scored. He was in an offside position when the ball was first passed to Iniesta, who started from an onside position. Navas was not called for offside at that moment because he was not actively involved in play in any of the three meanings defined by the International Football Association Board: interfering with play, interfering with an opponent, or gaining an advantage from being in that position. Navas remained in that position to show his lack of involvement as Iniesta moved forward. Navas became onside as soon as Iniesta took possession of the ball and moved nearer to the goal. Iniesta then passed the ball to Navas. By the time Iniesta passed the ball to Navas the latter was no longer in an offside position — never having moved or interfered with play or with an opponent (no one even looked at him) — and could not be called offside because he was level with the ball at the pass.

I might add that the television commentators, generally the least knowledgable observers of soccer at any level of play, got it right this time and never said a word about any offside.