Kyle Walker revealed his training-ground mocking of the Manchester City goalkeepers contributed to his unorthodox role at Atalanta, where he found life a little tougher than anticipated.
Right-back Walker ended the match at San Siro in goal after Ederson was injured and substitute Claudio Bravo was sent off in the 1-1 draw.
The England defender was introduced in place of Riyad Mahrez and donned the gloves, remarkably making the only save of all three City keepers from Ruslan Malinovskiy's free-kick following the foul that saw Bravo dismissed.
Walker saw out the remaining nine minutes and stoppage time without conceding, before reflecting on a bizarre outing.
Asked if he had made the decision to go in goal himself or been instructed to do so, Walker told BT Sport: "I think it was a little bit of both.
"I try to sometimes banter the keepers in training, telling them to catch it and stuff. But as I found tonight, sometimes you do have to take two touches.
"All jokes aside, we came here to get a point or a victory. We knew it was going to be difficult because they play man-to-man, they're a good team and they're in the Champions League for a reason.
"To come away from here with how we ended the game with a draw is a good point, and we'll take that on now."
Defensive colleague Benjamin Mendy thanked Walker for seeing City through a tense finale.
"I think tonight was a very tough game. We knew it before the game," he said. "And how we fought until the end to keep [a point], I say thank you to Kyle.
"It's not easy to take this responsibility going to be a goalkeeper and saving the free-kick. It's one game we're going to remember going forward in this cup."
Manager Pep Guardiola added with a smile: "We had a good first half, but in the second half we suffered a lot. In the last 15 minutes we had the situation we had with the new goalkeeper in our squad."