On a day when Donny van de Beek hoped to show why he deserves more minutes for Manchester United, up stepped Bruno Fernandes to show why that simply isn't happening.

The eye-catching selection of Van de Beek ahead of Fernandes for this FA Cup clash of giants at Old Trafford was all about "rotation", according to Ole Gunnar Solskjaer.

United's manager clearly felt his team could combat a faltering Liverpool team without their star man, albeit leaving him on the bench in case of emergency.

"Donny needs to be playing games as well and it's a big game for Donny to come into," Solskjaer told the BBC.

Van de Beek has not started a Premier League game since he was hauled off with United trailing at half-time at West Ham in early December, and he might not be starting any soon either given how this game transpired.

A 66th-minute switch of the Portuguese for the underwhelming Van de Beek proved pivotal, and the delightful free-kick from Fernandes that settled an absorbing game 3-2 in United's favour was one that had been conceived on Saturday.

"I think he stayed about 45 minutes after training yesterday shooting free-kicks, so I was quite confident that he was going to hit the target," Solskjaer said.

Solskjaer, the erstwhile supersub, knew the calibre of replacement that was up his sleeve, and the rotation worked in a roundabout way. Are we looking at more proof that United's once-maligned Norwegian boss is actually a tactical master?

Liverpool's season, meanwhile, takes another negative turn.

Donny fluffs his big chance

With a mere 18 passes and 23 touches, Van de Beek was peripheral in a midfield where Paul Pogba shone and Scott McTominay fought for every ball.

The former Ajax man had a glorious early chance to stamp his mark on the game when he burst into space on the right and looked sure to dart towards the penalty area, as Edinson Cavani waited for a pass in the centre.

But no. Van de Beek paused and decided to go backwards, and the chance was gone.

This game was a world away from the Anfield snore draw seven days previously in the Premier League, yet Van de Beek largely let it pass him by.

By the time Fernandes cracked his sublime winner into the right corner, Van de Beek must have been wondering when such an opportunity will arise again.

Salah shows he must start

Like Fernandes, Salah has seen his form and contribution questioned in recent weeks, and just as United's match-winner dispelled such criticism, so did Liverpool's main man.

After all the talk about front threes, and which of these sides had the most deadly attacking trio, Liverpool boss Jurgen Klopp went with a two-man strikeforce, Salah and Roberto Firmino linking up and Sadio Mane on the bench.

Both Salah and Firmino had been substitutes on Thursday for the defeat to Burnley, but they were a combination that United struggled to contain at times here.

Salah struck twice, the first a sublime chip, and Firmino set up both. The Brazilian has now assisted Salah for 18 goals during their time together at Liverpool, the most any player has set up another during Klopp's reign.

Unlike Firmino and Mane, Salah has exceeded his expected goals (xG) in the Premier League this season, with eight non-penalty goals from an xG of 5.3, and if Liverpool are to resurrect their season, the bench is surely no place for the Egyptian.

Glorious Greenwood

Mason Greenwood has not scored in the Premier League since that West Ham game, when he helped United turn their half-time deficit around and earn a 3-1 victory.

Here he looked lively from the early stages, albeit with one too many lollipops and insufficient tasty final product until he cancelled out Salah's opener.

The way the 19-year-old ended an 10-game barren spell spoke volumes of his belief, with Marcus Rashford's sweeping pass over the Liverpool defence finding his wing twin on the right and allowing Greenwood to thump a low shot past Alisson.

With Rashford also on target, this was quite a day to savour for the hosts.

Manchester United boss Ole Gunnar Solskjaer left Bruno Fernandes out of his starting line-up for Sunday's FA Cup clash with Liverpool.

Fernandes, who has been United's shining light since arriving from Sporting CP almost 12 months ago, was only a substitute for the fourth-round game.

This season he has scored 15 goals and supplied nine assists in 28 games across all competitions from his advanced midfield role, but there have been questions asked about his form in recent weeks.

He has just one goal and no assists in four Premier League appearances since the turn of the year.

Into the United team went former Ajax midfielder Donny van de Beek as Solskjaer decided the game presented a chance to rotate his squad, making five changes to the side that won 2-1 at Fulham on Wednesday.

Solskjaer explained why Fernandes did not start, saying on BBC One: "It's rotation in the squad.

"Donny needs to be playing games as well and it's a big game for Donny to come into.

"He's done nothing wrong when he's been around the club so I'm looking forward to seeing him in there."

Premier League leaders United also brought in goalkeeper Dean Henderson, centre-back Victor Lindelof, midfielder Scott McTominay and forward Marcus Rashford, as David De Gea, Eric Bailly, Fred and Anthony Martial dropped out.

Liverpool also showed five changes as Jurgen Klopp looked for a response to Thursday's shock 1-0 home defeat to Burnley, which ended a 68-game unbeaten run at Anfield in the Premier League.

Teenage centre-back Rhys Williams came in for the absent Joel Matip, while James Milner and Curtis Jones were selected as Xherdan Shaqiri and Alex Oxlade-Chamberlain dropped to the bench.

Sadio Mane and Divock Origi were also substitutes as Klopp gave starts to Mohamed Salah and Roberto Firmino, with the Old Trafford clash coming a week on from these two sides battling out a dreary goalless draw at Anfield in the league.

Manchester United boss Ole Gunnar Solskjaer says he can fully relate to Donny van de Beek's unhappiness after being used sparingly during his time at Old Trafford.

The Netherlands midfielder has made nine starts for United since arriving from Ajax for a reported £40million in the close season, just two of those coming in the Premier League.

He has not featured at all in United's last three games since the 1-0 FA Cup win over Watford on January 9, but he will play a part in Sunday's fourth-round tie against Liverpool.

Solskjaer himself found regular starts hard to come by during his playing days at the club under Alex Ferguson and has praised Van de Beek for remaining professional.

"I wouldn't say that Donny is happy," he said. "Of course, he wants to play more, but he gets about his job in the right manner.

"He reminds me a lot about myself, when I first came in, that he understands my difficulties and challenges

"We are doing well and have got players who are playing really well in his position.

"I was the same with Sir Alex. When he left me out I understood and I was happy for the team to win – and Donny is that type of guy."

Van de Beek has made 10 Premier League appearances for United in total and scored his only goal in the 3-1 win over Crystal Palace in September.

The 23-year-old has yet to assist a goal and has created just two big chances for his team-mates across those 10 matches.

His average of 50.2 passes per 90 minutes ranks below fellow midfielder Bruno Fernandes (60.17), Paul Pogba (62.02), Fred (62.85) and Nemanja Matic (76.08) but above Scott McTominay (48.37).

Van de Beek ranks higher for dribbles completed (1.43), however, with Pogba (1.75) the only midfielder above him in that metric.

Solskjaer continued: "He knows he is important for us and knows he is going to play many games.

"He will definitely be involved in this game against Liverpool and he might be the deciding factor in the game.

"He trusts his own quality. He is a quietly confident guy who deep down knows he is good enough and is just waiting for his opportunity."

Having been used in a variety of roles in United's midfield, Van de Beek – utilised as a box-to-box threat during his Ajax days – scored 28 goals in total in the Eredivisie. 

Arguably his most impressive form for Ajax came in the 2018-19 Champions League campaign, with his four goals helping the Dutch giants to the semi-finals.

Ole Gunnar Solskjaer has underlined his desire to keep Donny van de Beek at Manchester United despite a difficult start to his Old Trafford career.

Since arriving from Ajax in a reported £40million deal in pre-season, the Dutchman has made just eight starts in total, with only two of those coming in the Premier League.

That lack of action prompted Van de Beek's boss at international level, Frank de Boer, to suggest this week that the midfielder might need to move on in January in order to strengthen his chances of featuring in the Netherlands' European Championship squad.

However, Solskjaer has reiterated his faith in the 23-year-old and revealed he will be handed a rare opportunity to start when United face Watford in the FA Cup on Saturday.

"I've answered this question so many times," the Norwegian said.

"There are so many examples of players needing a little bit of time – quality players. We have many players ourselves and there are other clubs with examples. Sometimes it takes time. You don't expect people who care for him to be quiet at times, especially when they want the best for them.

"Donny is going to play tomorrow. There's another chance for him. Yes, I've spoken to him and reiterated and made him aware how much we rate him. But he'll play tomorrow, and that's a good chance to kick on."

One player who could be set for a January departure from Old Trafford is Timothy Fosu-Mensah.

The 23-year-old, who is out of contract at the end of the season, has made just three appearances this term, including one start.

And Solskjaer is open to the idea of allowing him to move on should the right offer arrive.

"I'm not sure if Tim is going to stay or [if] he's going to take an option now," he said.

"He's not played enough, so of course he's been allowed to speak to clubs, with a view to leaving now in January. It's difficult when you've got good players, talented players, and you can't give them game time.

"He's now at the stage where he needs to go and play again.

"It might be [at the] end of January, or it might be in the summer that he finds somewhere else. So, he's working hard, Tim, he's ready for a move for any club that he feels ready for."