He joined the party here in presence of its chief Uddhav Thackeray. Along with Nimhan, several other Congress leaders from Pune, who were once in the saffron outfit, returned to Sena fold.
Nimhan is known to be a staunch supporter of Congress leader and former Minister Narayan Rane, who left the saffron outfit in 2005.
The 51-year-old had been twice elected as Sena MLA from Pune's Shivajinagar Assembly constituency - in 1999 and 2004 - and retained the seat as Congress candidate in 2009.
Along with him, other leaders like Ravindra Phatak, Sada Sarvankar, Jayant Parab, Shrikant Sarmalkar, Raja Raut, Subhash Bane and Ganpat Kadam, too, joined the Sena, which is part of the BJP-led governments in Maharashtra and also at the Centre.