The most expensive deal done in soccer's January transfer window was also one of the more puzzling.

Willian signed with Russian club Anzhi in one of the most expensive and most puzzling soccer deals from January. Associated Press

Willian Borges da Silva, the 24-year-old Brazilian superstar known as Willian, represents a certain archetype: the one who leaves his country at a young age and moves for a big fee to one of soccer's nouveau-riche clubs in Eastern Europe. That's exactly what he did in 2007, when Corinthians ignored overtures from Europe's traditional powers and instead sold him to Ukraine's Shakthar Donetsk. The price tag, $19 million, was hefty, and with less than a full season under his belt, no club from Spain's Liga or the Premier League was willing to roll the dice on the 19-year-old talent.

The script then would have called for Willian to establish himself as a bona fide star on the European scene and clinch a lucrative move to one of the continent's big leagues. Yet it is a sign of the changing landscape in the European game that while the first part of the equation came to pass—Willian was outstanding for Shakthar in the group stage of the Champions League—the second didn't.

Here's what happened instead: On the final day of the transfer window, Willian ended up with a $48 million move to Russia's Anzhi Makhachkala, hardly a European blue blood.

Anzhi already boasts the world's highest-paid player in the world after taxes (Samuel Eto'o) and the best-paid coach in the game (Guus Hiddink). But it is tough to see the Dagestani club as anything other than a rich man's plaything bankrolled by the billionaire Suleyman Kerimov. He has spared no expense to build the team, but financially sustainable success seems a long way off, if not downright unattainable. For starters, because of political instability in Dagestan, Anzhi's players actually live and train in Moscow and only fly down on weekends for games. Kerimov is building a 45,000-seat stadium to replace Anzhi's 15,200-seat roofless bowl, but it is hard to see the new facility as an instant money-spinner: Makhachkala's population is less than 600,000, and Dagestan is one of the poorest regions of Russia.

And yet this will be Willian's next stop, despite his best efforts to go elsewhere. For the last 18 months, he had been hoping for a move, but Shakthar was unwilling to budge from its lofty valuation. He was pursued by half a dozen clubs over the last 18 months—including Chelsea and Tottenham—and was even willing to take a pay cut to facilitate a deal. But none of his suitors were ready to break the $35 million mark.

In some ways, trying to find a buyer for a player like him is a bit like trying to sell a $10 million mansion. It may be a great deal for someone, but the reality is there aren't that many buyers who are able to stump up the cash. What's more, Shakthar has its own deep-pocketed billionaire owner, Rinat Akhmetov, and therefore faced no real pressure to sell. Indeed, had it not been for a clause written into Willian's contract that set the release price at $48 million, it is likely the club would have demanded even more.

Still, it seemed like the logical thing for Willian to do was stay put until the summer. Shakthar is in the last 16 of the Champions League—it takes on Borussia Dortmund later this month—and there is no better shop window for a player to establish himself as a superstar and persuade buyers to kick in a few extra million. Come the summer, he also would have had just a year and a half left on his contract, giving him more leverage and contractual power.

But there were two problems with that approach. Even if Willian had a stellar second half, it was by no means guaranteed that a big club in a big league would meet his price tag. UEFA's Financial Fair Play regulations, which begin in 2014 and limit a club's losses over a given period, are turning soccer into a buyer's market in which habitual big spenders are unwilling to throw money around. Three of the wealthier clubs—Real Madrid, Chelsea and Manchester City—also could change managers at the end of the season, adding another layer of uncertainty to signing Willian. Others—like Manchester United, Paris St. Germain, Barcelona and Bayern Munich—already have a wealth of options in Willian's position. A number of Russian clubs are flush with cash (three of the seven biggest signings of this season were made by Russian teams). But the league places a limit on foreign players, so it was no sure thing that Anzhi would still have a slot for Willian had he waited.

The other concern was that was that Shakthar would offer Willian a new deal at some point in the next 18 months. Had he turned it down for free agency, he would have been frozen out. It is a tactic some clubs have used in the past and a risk he didn't want to take, especially not with the World Cup on the horizon.

Whether Anzhi offers a better springboard to jump to the Premier League or La Liga remains to be seen. The club is in the last 32 of the Europa League, which offers less exposure than the Champions League. With 11 games left in the Russian Premier League, Anzhi sits in second place. But the manager, Hiddink, has said he would retire at the end of the season (the club still hopes to change his mind) and its business model could be untenable in light of Financial Fair Play.

It's hard to sympathize too much for a guy who plays sports for a living and is a millionaire as a result. But in some ways Willian epitomizes the current state of flux at the highest level of the game: new money flowing in from the edges of Europe, most of the continent's nobility hunkering down in anticipation of Financial Fair Play, the rest knowing they can pick and choose in what's now a buyer's market of falling transfer prices.

—Gabriele Marcotti is the world soccer columnist for the Times of London and a regular broadcaster for the BBC.