The 25-year-old was recalled to Mikel Arteta's starting XI - his first Premier League appearance since September 3 - with David Raya ineligible to face his parent club.
And the goalkeeper almost gifted the Bees an early lead at the Gtech Community Stadium after he lost possession on the edge of the six-yard box.
He dithered with the ball at his feet, with Yoane Wissa robbing him of possession before playing the ball back to Bryan Mbuemo.
The Cameroon international arrowed a first-time effort towards the bottom left corner but, thankfully for the visitors, Rice sensed the danger.
He got back quickly to clear off the line, with Wissa then missing the rebound as the ball cannoned back to him.
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Despite the calamitous gaffe from Ramsdale, Manchester United legend Gary Neville believes his error is down to Arteta.
Ramsdale has lost his place in the line-up to Raya, with Neville declaring the ex-Sheffield United star is suffering as a result.
Taking to X, he said: "This is what happens when you have 2 keepers eating each other! You put them both under pressure."
Though the majority of fans believe the blame has to lie with the shot-stopper, with Neville's Sky Sports pundit Jame Carragher disagreeing with his view.
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He stated: "Arteta has created this pressure on his keepers narrative is nonsense!!!!!
"Arteta should improve on his goalkeeper if he feels it's right, is he supposed to sell the other one the same day."
Another messaged: "Such errors are inexcusable, no matter how you look at it. Thank you, Declan Rice."
This supporter commented: "Confidence is a weird thing. I feel for Ramsdale. Running out of compliments for Rice though."
Meanwhile another wrote: "That Rice save has me thinking Ramsdale might not even be our 2nd best keeper."
And this fan said: "Ramsdale… this is your chance and you're doing this. Come on man."