It can happen if the player wants and the club also wants. But Madrid has made a statement that Arda Guler will continue to play in Madrid, which means Ancelotti still needs him as part of the team's plan. He still has a little chance to play, he is still young and I think Ancelotti will give him more chances in the future. For now, he is fine in Madrid, maybe it would be very good for him to be the first choice in the squad that he can get in another club. But being a young player in the Madrid squad will not be easy.
Real Madrid has already stated that Arda Guler is an important asset for them, and any offer is likely to be rejected unless it is a loan option. But, if we look at how many players are prone to injury this season, it looks like Real Madrid will really need Guler at this time and it seems that Guler is also quite comfortable with his current situation. If Guler wants the big stage then he has to be patient, but if he is in a hurry then the only way is to leave Madrid (whether it is permanent or with a loan option).