Emile Smith Rowe gave the Gunners an early lead but United struck back before the half-time break thanks to a goal from Bruno Fernandes.
And Morgan, writing in his column for The Daily Mail, has now revealed he received a text message from Ronaldo after the final whistle.
“Arsenal played Manchester United and I sent Cristiano Ronaldo a desperate plea before kick-off, ‘Please don’t score against us…,'" he revealed.
“Of course, he scored twice, and United won 3-2. ‘Sorry,’ Cristiano texted back after the final whistle.
“I would have accepted the apology if it hadn’t also contained a laughing emoji.”
The ex-Good Morning Britain presenter, 56, struck up an unlikely friendship with 36-year-old Ronaldo after interviewing him in 2019.
Morgan has previously opened up about his close relationship with the Portugal star in previous editions of his weekly column.
Earlier this year, he wrote: "Our relationship began in the most random of ways when he sent me a direct message via Instagram three years ago, saying: 'Hello sir, how are you? I saw your murder documentary on Netflix. I find it fascinating to see you interview these murderers.'
"Once I'd got over the shock of one of my all-time sporting heroes contacting me out of the blue, I rapidly pulled myself together and put on my professional game-face.
"'I'd find it fascinating to interview YOU one day…' I suggested, putting out my fishing rod. I haven't killed anyone!' he replied.
"The real Ronaldo is warm, self-deprecating, generous, grounded and hugely liked by almost everyone who's ever worked with him or met him.
"Since meeting Ronaldo in late 2019, we've become unlikely mates. We speak on the phone from time to time and chat frequently on WhatsApp about everything from football and fast cars to yachts, coronavirus and fatherhood.
"I've met and interviewed a lot of sporting legends in my 30 years as a journalist and broadcaster. None has impressed me as much as Ronaldo, on and off the pitch."
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