Certain combinations work for the business of the film. It's not just the hero and the director, but the name of the music director also plays a vital role in setting up expectations on the project.
NTR-Anirudh was a combination that was planned for the film "Aravinda Sametha '' by Trivikram. This young lad has come to the opening of the film as well. But due to the Ajnatavasi effect, he was kept aside.
Thaman came into the scene eventually for Aravinda Sametha. Anirudh missed scoring music for NTR's film that way.
But in that gap, Anirudh scored music for some Tamil films that became chartbuster hits. The songs scored huge views on youtube and pulled global traction. So, he was brought on to the track by NTR for his film with Koratala Shiva.
Devi Sri Prasad was at loss with these developments. It was assumed that DSP will repeat to score music for this combination after Janatha Garage. But he missed it.
If Anirudh's music becomes a hit, then he will settle down in Tollywood working for all the big ticket films.