A peak of 10.3m viewers watched live BBC coverage of the Grand National on Saturday, the highest total since 1998.
Amberleigh House's trainer Ginger McCain also trained Red Rum
The race was won by Amberleigh House, who overhauled co-favourite Clan Royal on the run-in at Aintree.
The FA Cup semi-final between Arsenal and Manchester United earlier the same day attracted a peak of 7.3m viewers.
"We're pleased the BBC was able to offer viewers another super Saturday of sport," said BBC Director of Sport Peter Salmon.