The executive producer of both Victoria and Poldark has admitted he was worried when the dramas went up against each other on rival channels.
Damien Timmer said he did not believe there would be room for both lavish series when ITV scheduled Victoria - which stars Jenna Coleman as the monarch at 18 - directly against series two of the BBC's big hit, Poldark.
He told Radio Times: "We didn't think it would be possible for both to find an audience.
"Victoria was coming late to the party; it always felt like a high-risk strategy."
The two shows, both ratings winners, have been facing off against each other in the 9pm Sunday slot since earlier this month.
The series two debut of Poldark failed to dethrone Victoria when they first went head-to-head.
Consolidated seven-day figures, released by the Broadcasters' Audience Research Board (Barb) a week after the BBC programme aired, showed that the Aidan Turner-fronted show was viewed by 6.65 million overall.
Victoria beat its main competition, with consolidated figures showing a total audience of 7.75 million for the third episode of the series, broadcast at the same time as Poldark's season two launch.
Timmer continued: "Poldark fans were already massively engaged with the show, they love it.
"Yet Victoria has found its place, and they both exist happily."
But he joked that the battle for the Sunday night ratings - and the fact that it could run on for years - made him feel "really tired".
This week's Radio Times is on sale on Tuesday.