Who among the following Peshwas was popularly known as 'Nana Saheb'?

Balaji Baji Rao, Peshwa from 1740 to 1761 and son of Baji Rao I, was popularly known as Nana Saheb. Balaji Vishwanath was his grandfather and the first of the family to be Peshwa, and Madhav Rao I was his son and successor. The Nana Saheb of the 1857 revolt was a different person, the adopted son of Baji Rao II, and was not himself a Peshwa.