I really hope this won't happen but it could be a great setup for a Sasuke vs Obito clash.
Scenario : Kakashi fails to pwn/TnJ Obito or hesitates to kill him, but Obito does and throws him away to the other dimension. Meanwhile Sasuke has learned that the masked man is Obito and that he was one major causes of the Uchiha massacre, sees Kakashi and runs to him while Kakashi's reaction would be something like : "Sasuke...I'm so glad you..." takes off his mask and smiles. Then Obito comes from the other dimension, sasuke becomes mad, ready for revenge.
Although it isn't known if Sasuke cares about Kakashi really really much, don't forget that Kakashi always cared more about him and tried to help him more than Naruto or Sakura.
Scenario : Kakashi fails to pwn/TnJ Obito or hesitates to kill him, but Obito does and throws him away to the other dimension. Meanwhile Sasuke has learned that the masked man is Obito and that he was one major causes of the Uchiha massacre, sees Kakashi and runs to him while Kakashi's reaction would be something like : "Sasuke...I'm so glad you..." takes off his mask and smiles. Then Obito comes from the other dimension, sasuke becomes mad, ready for revenge.
Although it isn't known if Sasuke cares about Kakashi really really much, don't forget that Kakashi always cared more about him and tried to help him more than Naruto or Sakura.