Jul.4 (GMM) Paul di Resta has split with his manager, London's Telegraph newspaper reports.
Anthony Hamilton, the father of 2008 world champion Lewis Hamilton, also no longer manages his McLaren-driving son.
Journalist Tom Cary said Force India driver di Resta's split with Hamilton snr "happened some weeks ago" and "was not planned".
Cary added that the "situation between the pair remains delicate".
26-year-old di Resta, who has been linked with a move to Mercedes next year, was available for comment, as was 56-year-old Hamilton.
"The reasons for the split remain unclear," said Cary.