We might not all agree that it's a legitimate defence against racism, but nobody would doubt that Luis Suarez was an excellent player. Despite that, the question of whether Liverpool were right to refuse such a colossal offer from Arsenal for his services in September is still one worth asking.
Ajax, after all, made do fine without him and improved their team with the proceeds from his sale, far less than Liverpool were offered. Suarez has undoubtedly improved since then, but by how much will be apparent from Liverpool's results in the upcoming games.
They have not struggled in his absence, after all. They may have lost a disappointing game at Anfield against Southampton, but they were thoroughly outplayed, with the four centre-backs comprising the back four and disrupting the hosts' possession play the largest factor in the defeat. Over the course of the season so far, they still have more points than they might have anticipated.
The response from his defenders will be to state that he is capable of scoring from nothing, of winning a game that does not deserve to be won, just as Robin van Persie does for Manchester United, or Falcao, or Zlatan Ibrahimovic, or Edinson Cavani, the strikers whose league he would profess to belong to. This is debatable, however - Suarez's style, of dribbling, taking on defenders, rounding goalkeepers, and finishing late can give standard goalscoring chances the appearance of solo works.
The defence he will be facing today could include Rio Ferdinand, having played heavily recently and, on Sunday's evidence, badly suffering from the exhaustion. Ferdinand is increasingly slow on the turn, and susceptible to Suarez's style of attack, while his partner, Nemanja Vidic, notoriously struggled to cope with the direct running of Fernando Torres during the Spaniard's Anfield heyday. Alternatively, Jonny Evans could deputise, a player who has seen little action and could be rusty.
That, along with the obvious occasion of the rivalry, gives Suarez the ideal opportunity to shine. United's performances against Liverpool in recent years have not been great, so a victory at Old Trafford is far from unthinkable, but they will be desperate to get over Sunday's humiliation, and avoid defeat at all costs. With Robin van Persie also out of action, there will only really be one truly talismanic player on the pitch.
Liverpool's increasing number of attacking midfielders have not quite clicked so far, with Coutinho still performing some level below what many at Anfield would claim, Iago Aspas yet to find his feet, and Luis Alberto and Raheem Sterling still raw and marginalised. If they were playing glorious football, then there may be the potential for Suarez's reintroduction to cause some disruption, but this is at least one potential side-effect that Liverpool will be free from for the time being.
Despite that, it may have a bad effect on some other individuals, if not the unit as a whole. Victor Moses was Liverpool's best player against Southampton, but his style is very similar to Suarez, even if they play similar positions. Two direct runners is already something of a gamble - when Raheem Sterling and Daniel Sturridge are added to the mix, Liverpool have the potential to break a new record for a front four to go an entire season without passing to one another.
Yet one striker carrying a team can't be a permanent solution. Suarez can't fix the lack of depth at the back which caused Mamadou Sakho, never a left-back to begin with and below Alex (!) in the pecking order at Paris Saint-Germain despite having growin up with the club, to be floundering around the turf at the weekend. He can't turn Jordan Henderson into the player Liverpool thought they'd bought, or stop the waning influence of Steven Gerrard.
While rustiness might temper his effectiveness tomorrow, and the sample size of Liverpool's early form is too small to judge much from (as evidenced by the unsurprising surprise defeat to Southampton), visible improvement should be the minimum anyone would expect from a supposed £50m player being added to a functioning outfit. We don't often get the opportuntiy to compare a side like this and cut down on the variables - but as long as it's possible to imagine Suarez scoring great and plentiful goals, yet Liverpool not improving as a team, we can't make a true judgement on his value.