If Liverpool do eventually move on from Mo Salah, Wednesday's win over Arsenal is a reminder success will not be easy without him.
Their games in the US, missing some of the club's biggest names, were supposed to be a chance for the often overlooked in the squad to show they are ready for first-team football.
Instead, it has been a stark reminder of Salah's brilliance and how much they will miss him if he does leave at the end of his contract – which expires next summer.
Liverpool struggled in the opening few minutes in Philadelphia, gifting Arsenal two enticing chances, but when Salah broke an air of inevitability consumed Lincoln Financial Field. You just knew when he was in the right place at the right time he was going to turn the game.
It is unfair to expect a reserve or youngster to be able to do what Salah can, but even Arne Slot admitted after the game no one really stood out when this was their chance to do so.
Harvey Elliott and Fabio Carvalho combined beautifully for Liverpool's second goal but the ever-critical Slot pointed out Elliott "could have done better" on two or three other occasions, while we all know there is a chance Carvalho could end the transfer window at another club.
Senior players, including Virgil van Dijk, Trent Alexander-Arnold and Darwin Nunez, will come back from holiday knowing their back-ups have not put their places in the starting XI under too much threat and major transfers are not in the offing.
And looking further ahead, it means Liverpool will have to spend big if they have to replace the ever-impactful Salah, Van Dijk and/or Alexander-Arnold when their contracts expire in June, unless someone steps up soon.
'Arsenal squad fit and with a shiny new toy'
As for Arsenal, they leave the States with a squad that is fit and with a shiny new toy for Mikel Arteta to play with.
Riccardo Calafiori has already impressed his new team-mates with his ability and attitude, according to Martin Odegaard, and his debut is expected to take place in a friendly next week.
But similar to Liverpool, we are not leaving Pennsylvania thinking 'my word, youngster X or back-up Y looked like the next big thing'.
And yes, it is difficult in energy-sapping heat against Premier League opposition, but pre-season games are so vanilla you just want something new to get excited about.
For both of these teams it seems unlikely a spicy new sensation will break through in the opening weeks of the season, but neither manager will care as long as their returning Copa America and Euro 2024 stars come back from their breaks ready to rumble.