Moussa Konate. It was the best €2,600 Christian Constantin ever spent.

That's the fee the FC Sion chairman shelled out on deadline day in January to hire a helicopter to fly Konate into Switzerland to get his signing over the line. The deal for the Senegalese cost little more than €500,000 - which looks a steal now.

Chelsea and Arsenal, confirmed by his agent, Antoine Issa Kossoko, this week "are watching him". A fee in the region of £10 million is now being mentioned . For Constantin, the 22 year-old is proving a not so bad gamble.

That's not to say Sion played FC Krasnodar for chumps. Just as previously with Genoa, Konate flattered, but failed to deliver consistently. It's not been until this year, working with Sion coach Didier Tholot, that Konate's potential - and profile - has exploded.

In his three years in Europe leading up to his Sion move, Konate had managed just seven goals. But since arriving in Switzerland, from 35 games, Konate has fired in 21.

His form in the second-half of last season had clubs from across Europe banging on Constantin's door.

Tottenham, Newcastle United and Watford all made contact, along with German trio Schalke, Wolfsburg and Werder Bremen.

But Constantin wasn't looking for a fast buck and in consultation with Tholot, agreed to resist all offers for their new star.

"Moussa must continue to progress with us, then later he can enter a new level for him in the market," says Constantin.

"He has already taken a step forward, he must now perform at a higher level, and he knows it. As it stands, there is no need to consider offers that do not reflect the true potential of the player."

Constantin is convinced Konate is destined for greatness.

"Konaté must prepare himself to integrate himself at the appropriate time into a major European club, one of the top five."

Tholot is delighted with the chairman's stand, convinced Konate's game still needs to be polished.

"I think he'll see out the season," said the Sion coach. "Only a stupendous offer will change things."

Which is where Chelsea and Arsenal enter the picture.

Constantin turned down one offer of €7 million over the summer, insisting Konate would not leave for "less than €10 million". However, that price has since jumped, as Kossoko revealed this week, with an offer closer to €15 million now viewed as more suitable. And if Chelsea or Arsenal firm up their interest, the valuation is sure to increase.

"I'm focusing on Sion," insists Konate, dubbed 'Baba' by Senegal fans. "There has been contact and we'll see what exists. But the final decision is not left to me."

Indeed, it's no secret there is tension between Kossoko and Constantin. Konate's agent branded the Sion chairman a "dictator" over the summer as the offers began to arrive.

"Christian Constantin behaves like a dictator and, like all dictators, he walks to his mood. If you come across him one day in a good mood, the discussion is possible. But if it's the opposite, the discussion is closed."

Kossoko and Konate were shocked upon learning of claims that Constantin had granted a handful of rival agents a mandate to sell the striker.

"I would once again like to clarify that I have only one agent and adviser, who is Antoine Kossoko - in case some would still do not understand," snapped Konate at the time.

Since then, the tension has eased, though Kossoko's decision to go public this week does suggest he's hoping to flush out potential suitors ahead of the January market.

The Bundesliga has been mentioned as an ideal destination for Konate, but the influence of the Premier League is strong - particularly when mixing with his Senegal teammates. Stoke City striker Mame Biram Diouf is close to Konate, who regards the former Manchester United attacker as a "big brother".

"Mame Biram is a big brother and I learn a lot at his side. He keeps giving me advice and it is a pleasure to play with him," says Konate. "My partnership with him will be explosive."

As Konate hints, the Sion striker isn't short of self-belief.

"Can I do better than Didier Drogba and Samuel Eto'o? They won everything. They were both strong and continue to prove themselves at their respective clubs.

"Today, my dream is to do better than them. I know how much they have achieved since the beginning of their careers."

Better than Drogba? Even if he only manages half of what the Ivorian achieved, that January chopper ride would be the best €2,600 Constantin has ever spent.