Newport delivered an FA Cup giant-killing act against Middlesbrough before goalkeeper Joe Day sprinted off the Rodney Parade pitch to attend the birth of his twins.
Second-half goals from Robbie Willmott and Padraig Amond secured County a fifth-round home tie with Premier League champions Manchester City on February 16.
Day had missed the first game with Middlesbrough, a 1-1 draw at the Riverside, to be with his wife Lizzie, but the 28-year-old made himself available for the Rodney Parade replay.
"I don't know if she's gone into labour but the way he sprinted off I'd say there's a very good chance," said Newport manager Michael Flynn.
"He did turn off his phone off before the game and he was fully focused.
"As soon as the whistle went he ran up to me and said could he go. I said 'Of course you can, do you want a lift?'
"He sprinted off, it's the quickest I've seen him move, and all our thoughts are with Joe and Lizzie and the arrival of the twins."
Newport have established an FA Cup giant-slaying reputation under Flynn in the last year or so with wins over Leeds, Leicester and now Middlesbrough.
The Exiles also held Tottenham 1-1 in the fourth round last season before losing a Wembley replay, but Flynn admits coming up against Pep Guardiola and City represents the pinnacle.
"This is the creme de la creme," said Flynn, who counts City's assistant coach Mikel Arteta as a friend after the two men were on the same Football Association of Wales coaching course.
"It's overwhelming and massive for the club. Pep is a master, somebody I idolise.
"He's probably the best in the business, although I am going to say along with Jurgen Klopp because I am a Liverpool fan.
"I know Mikel and he's just messaged me to say 'See you soon'.
"He's a fantastic guy, we did our Pro-Licence together, and it shows how down to earth he is."
Flynn said he saw City beat Arsenal on television on Sunday when he should have been at a children's party with his wife.
City's passing game might be challenged by the pitch that Newport share with the Dragons rugby team and tends to cut up.
But Flynn, who says the Sky Bet League Two minnows will bank over £1million from this cup run, said: "Knowing how good Pep is I'm sure they'll overcome that pitch.
"They are outstanding. I wish I hadn't watched that Arsenal game now, because they were absolutely breathtaking.
"We'll have to be prepared, and I might play nine at the back!"
Boro's defeat marked a sad homecoming for manager Tony Pulis, who was born in the Newport district of Pillgwenlly just a few miles from Rodney Parade.
"They dominated the game in every aspect," said Pulis, whose side are fifth in the Championship and boast the best away record in the division.
"It was a bad night but I don't want to take anything away from Newport, they were much better than us all over the pitch.
"If we'd been a little bit milky away from home this season, and lost a lot of games, I would have come here thinking 'what's going to happen?'
"But the lads haven't done that and been brilliant away from home, so as much as I'm hurt you can't criticise this team too much."
