The pair of young wing-backs have impressed in the Carabao Cup this season but have had limited opportunities in the Premier League.
That is, however, until Ait-Nouri came in for the injured Fernando Marcal on Saturday and did well – while Hoever came on as a late substitute.
And Lage says first choice Marcal and Nelson Semedo are under pressure to keep their place with the two youngsters pushing them.
When asked how he keeps the pair motivated with a lack of Premier League minutes, Lage said: “That’s the job, we never know when they’ll have the chance.
“I was happy with them against Tottenham, they did well, and that’s what we want.
“In the same way, we have four wingers in Daniel, Trincao, Hwang and Adama to fight each other and we have those kind of roles in the right and left-back.
“They are causing a lot of problems for Semedo and Marcal. For sure, when they go home they dream about them, because they are working hard every day.
“We never know when they’ll have the chance but what I want, is when they have the chance, that I feel they are ready.
“Against Southampton Ki needed to play two or three minutes and he was ready.
“Every time I want everyone ready to help the team, to start in the first XI or to start from the bench.”