Sir Alex Ferguson was impressed with the duo in a recent clash against Arsenal at Moss Lane, suggesting they had future first-team potential, and the youngsters will be looking to continue to progress during the remainder of the season.
Powell, who joined the club in the summer from Crewe, scored both goals in Wednesday's win against West Ham with Januzaj playing just behind him in an advanced midfield role during the 2-0 triumph.
"Adnan is a beautifully balanced player," Sir Alex told Inside United. "He's only 18 and still to grow into his frame. But he has good balance, good acceleration and he's a very good technical player.
"He and Nick, of the younger players, are at the top. They're very good.
"Nick has had a few injuries and has had a bit of bad luck so we feel Carrington is the best place for him at the moment [rather than sending him out on loan]. That way, we can work on bringing him on physically and preparing him for next season."
Meanwhile, Reserves coach Warren Joyce has also spoken about the talented teenagers as he works closely with the pair.
"Nick's got talent," he told ManUtd.com. "He can play anywhere on a football pitch as he's got really good ability.
"Adnan is still developing but there's no doubt he's got talent too. He's got a good footballing brain and a good touch. We're trying to get him