Later, Munenobu was called 'Chuko no so, the Matsui clan of Totomi Province' with respect for his faithfulness since he contributed to the prime of the Imagawa clan as castellan of Futamata Castle and fiercely defended his lord while being killed in the Battle of Okehazama.
二俣城主として今川氏の最盛期に貢献し、桶狭間の戦いで主君を守るため壮絶な戦いを繰り広げ戦死した宗信は、後世、その忠節への敬意も含め「遠江国松井氏中興の祖」とも呼ばれる。