Nehra and Mohammad Kaif would fly to Lahore to join the team before the start of the second cricket Test beginning on April 5, BCCI sources said.
Nehra was being sent to Pakistan in view of a recurrence of the injury problem of Zaheer, who is yet to bowl to his potential in the historic series.
Zaheer has already been advised a scan as his right hamstring problem, which forced him to return from Australia midway through the series, was again troubling him.
Nehra, who had bowled brilliantly in the first two One-dayers of the current series, had to return home after he hurt himself during the second match at Rawalpindi. He has now recovered.
Kaif was being sent to strengthen the batting in the team after skipper Sourav Gangly hurt himself in the fifth One-dayer and was ruled out of the first two Test matches.
Ganguly arrived in Kolkata on Thursday evening for treatment by a specialist orthopaedic and is expected to re-join the team for the third Test beginning on April 13.