Director-producer Sanjay Leela Bhansali's 'Bajirao Mastani' has Ranveer as Peshwa Bajirao and Deepika playing Mastani. It features Priyanka Chopra as Kashi Bai, the wife of Bajirao.
"The action in the film is very authentic. You can't compare it with the modern day or past. We had to keep it real. The technique is modern but the way of doing it is old," Kaushal told PTI in an interview here.
The 59-year-old action director has worked with both Ranveer and Deepika in several films but said the dedication the two actors brought for "Bajirao Mastani" was commendable.
"Deepika is dedicated, committed and intelligent. She gets into nitty-grittes. It is not easy to portray 'Mastani'.
When going for war sequences she has to show softness on her face and be strong at the same time. Deepika surprised me... She has never done that kind of combat action earlier," Kaushal, who has directed the action sequences of "Krissh" franchise, said.
For Ranveer, whom he has worked in action-drama "Gunday", Kaushal said had to tell Ranveer to mellow down.
"...Bajirao has to be rough and a hard man. With Ranveer, I had to tell him to control his energy. His energy is inbuilt we don't have to tell him to charge up ever.
They both have done a great job," he said. "Deepika is like daughter to me and I call Ranveer, Tiger.
They are like my kids. They have faith in me... We share a great rapport. They are hard working." Ranveer injured his shoulder while shooting for "Bajirao Mastani".
"It was in February when he got injured. He fell down from a horse. He injured his shoulder..It was an unfortunate incident. When he came back to shoot after four-five months we all behaved as if nothing had happened, we appeared normal," Kaushal said.
The much awaited film opens in theatres on December 18.