There were two big stories in Belarus in the last week of July. On the plus side, their premier, Alexander Lukashenko caught a catfish bigger than the pike Vladimir Putin had landed in Siberia a few days earlier. More difficult to comprehend, though, was the news that Uralkali, a Russian firm run by Suleiman Kerimov, had broken off a business agreement with a Belarusian company that effectively fixed global potash prices. It's hard to say precisely what the consequences will be, but pressure has already been placed on the Belarusian rouble, while a surge in the supply of potash should lead to a decrease in the cost of fertiliser (and thus perhaps food). It could also lead to the sale of Samuel Eto'o to Chelsea.

Quite why Uralkali have ended what was effectively a cartel is unclear, but in the day that followed the announcement, £5.5bn was wiped off the company's stock market valuation, with Kerimov himself losing an estimated £325m. The share price has since recovered and a direct link between the end of the agreement and what is going on at Anzhi Makhachkala has been denied, but that Uralkali felt compelled to take such a drastic step hints at the turbulence behind the scenes.

What has happened at Anzhi is a warning to all clubs who rely on external investment. The club, which had been founded in 1991, had worked its way into the Russian top flight when, in January 2011, it was taken over by Kerimov. He was born in Derbent in Dagestan and studied accounting and economics at Dagestan State University and has always insisted he took over the club for reasons of local pride, although it's no secret that Putin encourages oligarchs to invest in sporting ventures as a way of returning some of their wealth to the people. Kerimov's investment in a club in such a troubled region fitted exactly into Putin's more general policy of decentralisation. There has been a conscious attempt, in all spheres, to reach out to the regions and it is no coincidence that after years of Moscow domination, there were five Russian champions in a row from outside the capital before CSKA's success last year.

Anzhi, despite eyebrow-raising deals to sign Roberto Carlos, Eto'o and Christopher Samba, and the appointment of Guus Hiddink as manager, never really threatened to join Zenit St Petersburg or Rubin Kazan on the provincial roll of honour. So Kerimov did what oligarchs usually do and spent some more. Around £50m was invested this summer, bringing the Russia captain Igor Denisov from Zenit, Aleksandr Kokorin from Dynamo Moscow and Samba back from Queens Park Rangers. Hiddink left to be replaced by René Meulensteen, who had limited experience as a No1 but who had gained a glowing reputation in his time at Manchester United.

The season, though, began badly. Anzhi took two points from their first four games. Denisov, a fine player but never the easiest character, fought with Eto'o and Lassana Diarra on the training pitch and was exiled to train alone, with rumours he could be sold to Dynamo. And then, last week, came the shock announcement that Kerimov was changing tack, slashing the club's budget from £116m per season (second only to Zenit in Russia) to between £32m and £45m.

It was portrayed initially as though Kerimov had grown tired of squabbling stars and was choosing to switch philosophy and start focusing on youth development – which even for a capricious oligarch would have been a bizarrely whimsical response to a few bad results at the start of the season. Clearly there are deeper reasons. Kerimov's spokesman has insisted that rumours the 47-year-old is in ill health are unfounded but it's hard not to see significance in the fact that the announcement of Anzhi's budget cut came just a week after the end of the Uralkali deal with Belarus that guaranteed a steady stream of income.

In practical terms, a £35m budget should still be enough for Anzhi to challenge for European places, but it has meant the end for Meulensteen, laid off after 16 turbulent days in the job (presumably soon to be the subject of a David Peace-Danny Boyle collaboration, 28 Days Shorter), and it also means that the highest-paid stars are likely to be offloaded. The querulous Denisov, who spent a substantial part of last season training with Zenit's youth team after protesting against the signings of Hulk and Axel Witsel, will surely go, and so too will Eto'o, who had previously demonstrated a clear reluctance to work for Gadzhi Gadzhiev, who has returned to the club to replace Meulensteen.

Eto'o's move to Russia has meant him disappearing from view in western Europe, and leading to the widespread assumption that he is over the hill. He certainly is not quite the player he was three or four years ago, but at 32 he still has much to offer, the intelligence that always underlays his game beginning to emerge as his pace diminishes. He has a year left on his contract so presumably wouldn't be overly expensive, although he would probably have to accept a pay cut to move to the Premier League and the fact his world record salary was paid in full in advance complicates matters.

Chelsea's interest in the forward is logical. The courting of Wayne Rooney suggested José Mourinho wasn't happy with his striking options – Fernando Torres, Demba Ba and Romelu Lukaku – and he has worked successfully with Eto'o before. The Cameroon striker himself makes no secret of his admiration for Mourinho and perhaps fancies one final crack with a major western European team. And if agreement can be reached on wages, it may be that, for all Lukashenko's and Putin's angling exploits, it's Mourinho who ends up landing the really big fish.