Rafa Benitez says it was important to give Sammy Ameobi and Jamie Sterry run-outs against Rotherham United.
The former Academy pair came off the bench in Saturday's 4-0 Championship win over Rotherham United.
Ameobi and Sterry – who are cup-tied and unable to play in Saturday's fourth-round FA Cup fixture against Oxford United – returned from half-season loan spells at Bolton Wanderers and Coventry City this month.
"Obviously, they are cup-tied, so they I couldn't use them (against Birmingham City last week), but they are training well," said Benitez.
"I think it's important for them to play and for the fans to see them and also to give a rest for the other players that were a little bit tired."
Forward Ameobi replaced Yoan Gouffran in the 63rd minute, while defender Sterry came on for DeAndre Yedlin late in the game.
"It's important to manage the squad because we play so many games in a few days that we need to give time to everyone," said Benitez.
"We must try to prevent problems and injuries.
"To see these players on the pitch and doing well is positive for the club."
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