Claudio Ranieri believes Ole Gunnar Solsjkaer "deserves" to be appointed Manchester United's permanent manager.
The Norwegian has excelled since succeeding Jose Mourinho on a caretaker basis, overseeing nine victories from 10 matches, and remaining undefeated to transform the club's season.
Saturday's fixture at Craven Cottage represents the start of a period that is expected to influence whether Solksjaer remains at Old Trafford — in the coming weeks they also face Paris Saint-Germain in the Champions League, Chelsea and Liverpool.
Ranieri, who arrived at the London club a month before Solskjaer returned to Manchester but who has struggled to have anything close to the same positive effect as the 45-year-old, said: "At the moment he deserves it. He's shown all the players are with him.
"Manchester United's mentality has changed. Why not?
"I remember him as a player, against Chelsea. He was a fantastic player. His career's open, and I wish him all the best."
Ranieri, however, feels that "sooner or later (United) have to lose", adding: "Why not against us?"
The Italian said: "We must be positive and we have to fight. If we don't fight and lose, you lose before you play.
"If the opponent is better, well done to them. I want to see my players fight until the end. My fans will be happy seeing the players fight for every ball."
Saturday's fixture could also reunite Ranieri with Anthony Martial. As Monaco manager, he engineered his arrival at the Ligue 1 club for a remarkably low fee two years before his departure for what could eventually cost United £58million.
"I signed him for £5million, it was good business," said the 67-year-old. "He was fantastic. I watched him during the Under-21s match against Monaco and was impressed.
"When the chance came to buy, I said 'Take this guy because for me he could have a good future'. He came to Manchester and well done to him.
"He's very good; can dribble; strong; fast. There are so many good players, (Paul) Pogba, (Marcus) Rashford; so many. We must be concentrated and strong, positive to show our personality during the game."
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