Southampton midfielder James Ward-Prowse and Chelsea winger Callum Hudson-Odoi have been called into England's squad for this month's European Championship qualifiers after four players withdrew due to injury.
The 18-year-old Hudson-Odoi was set to join the Under-21 squad in Bristol when he was told he had received his first senior call-up.
"It's been a crazy day but getting my first [senior] international call-up is an amazing feeling," Hudson-Odoi said.
"I'm delighted to get the call... I thought the [Under-21] manager [Aidy Boothroyd] was joking. I was shocked and then when I heard that I actually had to go over, I couldn't believe it."
The FA also announced Ward-Prowse was added to the squad in a statement: "James Ward-Prowse has been called up to the England squad ahead of the UEFA EURO 2020 qualifiers against the Czech Republic and Montenegro."
Ward-Prowse, 24, claimed one senior cap two years ago when England lost 1-0 to Germany in a friendly. He has scored six league goals for Southampton this season, including two free kicks against Manchester United and Tottenham Hotspur in his last two Premier League games.
England play Czech Republic on Friday at Wembley Stadium and face Montenegro on March 25.
Updated England squad:
Information from Reuters was used in this story.