Alexander Isak and Florian Wirtz have only started eight games together for Liverpool. As Mohamed Salah waved goodbye to the Anfield crowd on Saturday after getting injured, the manner of his reaction and that of all those in the ground suggested that deep down, both player and supporters knew it could be the final time.

Thankfully for Liverpool supporters, the side's manager Arne Slot confirmed on Friday the Egyptian is expected to return to action before the end of the season after sustaining a minor muscle injury. For now, what is certain is Liverpool will head to Old Trafford this weekend without the man that has a formidable record against Manchester United. With 13 goals in 16 games against United, no player has scored more than Salah in the Premier League era against them. Against the other five 'big six' teams in the Premier League, Salah has contributed a mammoth 49 goals and 22 assists for the Reds.

Without him, Liverpool need others to take responsibility, and notably the focus will intensify on Alexander Isak and Florian Wirtz as they take on United, Chelsea, and Aston Villa over the next fortnight. Put simply, both need to step up after a challenging season, and Slot knows part of his tenure will ultimately be judged on his ability to get the best out of the two most expensive signings in Premier League history.

In the aftermath of Liverpool's Champions League exit to Paris St-Germain, Slot insisted the future is bright. Eyebrows were certainly raised after that comment, but if Liverpool can put in a string of performances in their remaining games, then perhaps the Dutchman has a point. Integral to that will be Isak and Wirtz.

Last Saturday saw both of the summer signings, who cost a combined £241m, score against Crystal Palace, but Isak is yet to complete 90 minutes as a Liverpool player after a season plagued with injury, while Wirtz has impressed in moments but is still awaiting a statement performance for the side.

German Wirtz is yet to score or provide an assist against any of the Premier League teams currently occupying the European places, but when that was put to Slot on Friday, he insisted that's a "coincidence" and said he is "100% sure" Wirtz will start delivering in the bigger games. Meanwhile, Isak managed just 18 touches against Palace, but that was still more than the nine he got against Everton and the five against PSG in the other games he's started since returning from injury.

The goal he scored - the Swede's first in the Premier League for Liverpool at Anfield - will only do the 26-year-old's confidence a world of good. "In terms of what I've seen, everyone knows and sees and experiences as team-mates how outstanding he is. It is about getting games, confidence, but obviously scoring goals as a striker – that's the main trigger for him," said Liverpool centre-back Virgil van Dijk.

"The more he touches the ball, the bigger chance there is that we score goals," Slot added on Friday. "Having Alex more and more available would help with converting created chances into goals, which is something we haven't done very well this season."

For Wirtz, the emphasis on connecting more with Isak is clear, especially with Hugo Ekitike sidelined. "It's important that we feed him with balls because if he's just there on top alone then it's hard for him to score goals," Wirtz said. His own tally of seven goals and 10 assists this season is certainly no room for major concern, but Wirtz, who turns 23 on Sunday, would be the first to admit that he must do better. The finish against Palace was a timely reminder of his class.

In mitigation, he initially struggled with the intensity and physicality of Premier League football but has bulked up considerably since making the move from Bayer Leverkusen. Those at Liverpool, including Slot, believe there is so much more to come from a player they fought Bayern Munich and Manchester City for.

"The development Florian has made in his Liverpool career is so clear and obvious," said Slot. "In the 93rd minute against Crystal Palace, making a duel on the sideline, winning a throw-in, and then making a sprint from 40 yards and hitting the ball in the top corner... That is something I am not completely convinced he could do eight months ago. His improvement - and he was already an elite player – will only continue as he is only 22 so that makes complete sense. Almost every player in the world is at his best when he is 25, 26 but he is already an elite player and he can only become better, and that is the beauty of the signings we did last summer, that all of them are of a certain age where we can only expect them to get better."

There will certainly be more incomings in the summer with Liverpool linked with RB Leipzig's Yan Diomande, who can play on both wings, but they will face competition from a host of other European clubs for the 19-year-old. The arrival of another quality winger should help Isak and Wirtz next season, but in the here and now lies a wonderful opportunity for the pair to start living up to the expectation they arrived with.

"We can be on a much higher level than we are now," said Slot on Friday. Victory on Sunday at their arch-rivals would see Liverpool go up to third on goal difference, which would be quite the feat considering the lows they have endured this season. Champions League qualification is all but secured, but it would also act as some form of proof that if this is Liverpool during their struggles, then what could be possible if they can get things to click and the likes of Wirtz and Isak can start to fulfil their immense potential? That's a big if - but a promising prospect indeed.