Both shows aired during the same 8pm to 9pm Sunday timeslot over the weekend – much to the annoyance of Simon – and it's emerged that Strictly narrowly pulled out ahead over its singing rival.
According to ratings figures, BBC One's Strictly had 8.4 million viewers with a peak of 9.4 million, while X Factor had 7.6 million with a peak of 9.2 million.
Simon has now reacted via Twitter, saying: "So, the numbers are in. Strictly peak 9.4, X Factor peak 9.2. Round one to them.
"Such a shame they were both on at the same time!"
Simon had already expressed his disappointment at BBC One's scheduling against his ITV show, suggesting they could have altered their timeslot to allow both shows to go out at different times.
"They [the BBC] didn't have to put it on at the same time as us but they did, and it means people now have to make a choice, whereas before it was more of a gentleman's agreement," he told The Independent.
"I always think that when producers do that, the people they are p**sing off are the viewers. They say that this isn't a ratings battle. It is. That's why they did it. When you know you've got two of the most popular shows of the year, it doesn't make sense to me to make the viewers choose. It's not a smart thing to do in my opinion.
"But it just shows the producers of Strictly Come Dancing for what they are. They don't want this show to do well; they don't want people to watch it. Our job is to do the best we can, so people prefer The X Factor to them."
However, a spokesperson for Strictly later countered by saying BBC had to schedule the dance show in the 8pm slot as ITV had scheduled an episode of Corrie to the schedule that night.
"We always try to avoid direct clashes but it's important that Strictly launches in prime time and with the extra episode of Coronation Street coming in, it's unfortunately left us with very little room to move on this occasion."
Sunday night's episode of X Factor continued the room audition stages in front of the judges, while the Strictly episode was the launch show.
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