Concurrently he progressed with his PhD program as a part-time Research Scholar under the guidance of Dean Professor / Dr PK Narayana Pillai, in the Department of Oriental Studies,[21] University of Kerala.

In May 1963 he joined as the only Lecturer in the University's newly established Department of Linguistics and in 1965 submitted his PhD thesis entitled Descriptive Grammar of Krishnagatha[24], one of the oldest and classic poetic works by the legendary Malayalam poet Cherusseri Namboothiri.

In 1967 Dr Nayar was granted a Commonwealth Scholarship for research in Phonetics and Linguistics at the School of Oriental and African Studies in the University of London.

Rejoining his parent Department in Thiruvananthapuram, Dr Nayar was promoted as Reader and subsequently as Professor and in 1981 as Chair-Professor, which position he held till his retirement in 1998.

During his tenure as Professor of Linguistics in the University of Kerala, Dr Nayar organized a number of Seminars, Symposiums, Conferences and Workshops at the regional, state and national levels and successfully completed several Research Projects.