United welcome the Championship side to St. James' Park (5.30pm kick-off) with a place in the fourth round at stake and the hosts seeking an immediate response following Wednesday's 2-0 defeat at the hands of Manchester United.
And Benítez has indicated he will give some members of his squad the chance to stake their claims for a more regular spot in his team this weekend – though he expects them to "show something" against Tony Mowbray's charges.
"For us, we have to approach the game trying to win with the best team possible that we can use, using at the same time players who have not been involved," he said. "They have to show something, they have to work hard, and I want to keep the good atmosphere in the dressing room.
"That means that players who don't have a chance in the Premier League, some of them will have a chance now, and they have to be ready to prove that they can play. If we go through, they can play more games, so I think it's just the right approach at the moment."
The United manager revealed that Mo Diamé will miss the tie with Rovers after picking up a knock in midweek.
Federico Fernández and Karl Darlow are also not yet ready to return, though the Magpies will be boosted by Ciaran Clark's return from injury.
And both Florian Lejeune – fit again following a cruciate ligament injury – and Sean Longstaff are available, with Benítez challenging his team to seize the chance to both perform and taste victory in front of their own supporters.
"I told the players that it's an opportunity for us to do well. We will play at home and we have to change things at home, so it's an opportunity to do that," he said, having seen the Magpies suffer defeat eight times at St. James' this term.
"Can we do it? I hope so, but at the same time, what I said is the players have to realise that they have to compete for every position. That is the opportunity they have."
Blackburn come into the contest on the back of an impressive 2-1 win over West Bromwich Albion on Tuesday.
And Benítez warned that Rovers – who could hand former United forward Adam Armstrong a start against his old club – will be giving their all as they look to claim a top flight scalp.
"They are doing well. They were improving. Our analysis department normally have three or four games (to watch), and they are doing well," he said. "They are scoring goals from different things – set pieces, counter attacks – and they move the ball quite well between the lines. They are a team who are doing well.
"Obviously, if they play against a Premier League team they will give everything, and it will be difficult. We know how difficult these kind of games are, but we have to do our best too."
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