Android Ameca – which creator Engineered Arts says is the “world's most advanced human shaped robot” – opened Thursday’s (18 May) instalment of the ITV show and was later interviewed by the presenters.
Willoughby and Schofield, who have been close for a long time but are now said to have fallen out, asked the robot for its best joke and also whether it wanted to take over the world – which it insisted it didn’t.
Viewers quipped that Ameca could fill in for the TV stars.
“Could the robot host perhaps??,” one fan posted on Twitter.
“It that Holly & Schofield’s replacement?” asked another.
One joked: “I think @thismorning have found a replacement for Holly, the AI robot Ameca.”
“Robots would make much better presenters,” another viewer teased.
Many others thought the segment was “terrifying”.
One tweeted: “I’m not sure about Ameca if I’m honest. Spooky.”
“Watching that AI robot Ameca tap its nose and then wink at the camera while Phil & Holly discuss with its inventor the potential of its world domination wasn't freaky at all,” said somebody else.
Another posted: “Creepy robot s*** going on in This Morning studio today. It blinks ffs, these things will kill us all!!!”
Willoughby, 42, and Schofield, 61, have been friends for more than 15 years but lately there have been reports of trouble between them.
Schofe - who recently took some leave around his younger brother's Timothy's sex abuse trial — addressed the gossip earlier this month, saying Willoughby was his “rock”.
He told The Sun in a statement: "As I have said before, Holly is my rock. We're the best of friends - as always, she is an incredible support on screen, behind the scenes and on the phone."
Schofield said Willoughby, who was recently ill with shingles, had always been there for him "through thick and thin".
"And I've been there for her," he said.
"The last few weeks haven't been easy for either of us."
Watch: Phillip Schofield and Holly Willoughby booed at NTAs