England Under-21 boss Aidy Boothroyd says Nigeria could still be trying to take his top talent.
The Young Lions manager remains on alert after reports Tammy Abraham was considering switching allegiance to the Super Eagles.
Swansea's on-loan Chelsea striker Abraham quickly denied the claims last month and reiterated his commitment to England, while Nigeria also made an approach for Liverpool's Sheyi Ojo last year.
Arsenal's Alex Iwobi elected to commit to Nigeria in March 2016 and -- ahead of Friday's Euro 2019 qualifier against Scotland in Middlesbrough -- Boothroyd conceded the country may try their luck again.
"Yeah, and they still might be trying -- you don't know -- but you can't blame them because they're good players," he said. "These are lads who have played for England who have an affinity with us and a relationship. When it happens with Sheyi I can pick the phone up, the same with Tammy.
"It's a hard one. I can't guarantee they are going to play because the group is so good. Tammy didn't start the game before last but that's just one of those things. Perhaps other countries will see that and get into him, promise him the world and get him in the first team.
"It's an interesting one (with Abraham). I saw like you all did on the TV. The good thing is we have a relationship and I can pick the phone up and say 'what's going on mate?'
"He laughs and says he doesn't know where it came from but it certainly didn't come from him. Twenty minutes later it comes across in yellow again: 'Tammy Abraham says he's going to play for England.'"
Abraham could spearhead England against Scotland at the Riverside Stadium as they continue their Euro 2019 qualifying campaign after drawing in the Netherlands and beating Latvia in their opening two games.
They play in Andorra on Tuesday in Group Four but Boothroyd is wary of Scotland, who are a point and a place behind his second-placed side.
Boothroyd added: "It's not a six-pointer but it's one of those you're desperate to win, and so are they. One, because it's England, and two, because it's the group which won the [Under-20] World Cup [in June], they'll be wanting to get one over on them. It's a bit like 1966 when we won the World Cup."