New Earth, the first episode of series two, averaged 7.99 million viewers and a 38.6% audience share for BBC One between 7.15pm and 8pm. The numbers were good enough for first for the day but were down on the 9.4 million who watched the Christmas Day special and also down on the 10 million who tuned in to last year's opener.
"We're really thrilled with the ratings," said a BBC spokesperson. "This is a brilliant start for the new doctor."
ITV1's premiere of the second Harry Potter movie, The Chamber Of Secrets, undoubtedly stole away some of the Doctor's viewers, putting in an average of 4.95 million (25.6%) between 6.40pm and 9pm.
BBC One managed a strong night overall, meanwhile, bookended by episodes of Graham Norton's Strictly Dance Fever, with audiences of 3.83 million (22.5%) and 3.9 million (23.6%) respectively. Casualty was the day's number two with 7.03 million (32.8%) at 8.35pm.
Elsewhere, BBC Two's coverage of the Snooker World Championships averaged a respectable 1.83 million (8.5%) over two hours from 7pm, topping C4's documentary The Passion: Films, Faith and Fury with just 890,000 (4.4%).
The success of Doctor Who carried over into multichannel homes, with 730,000 tuning to BBC Three at 8pm for spinoff show Doctor Who Confidential.