The wrong 'un... and a price tag of £26,400: What happened to Garry Sobers' six sixes ball?

Howzat possible? How could a cricket ball that was supposedly smashed around St Helen's in Swansea for six sixes by Garry Sobers in 1968 be sold for a staggering £26,400 when it wasn't the right make?

A Duke instead of a Surridge? That blatant discrepancy just didn't make sense and launched my 18-month investigation into the controversial sale of cricket's most famous ball at Christie's in 2006.

I was writing Six of the Best, a 40th anniversary celebration of Sobers' feat. I knew the Duke had been consigned to Christie's by Jose Miller, a former secretary of the Nottinghamshire Supporters' Association. She had received it from her predecessor, John Gough, who in turn had been given it by Sobers in 1968, and her name cropped up in a phone conversation I had with Sobers' then agent, Basharat Hassan, in March 2008. He had arranged for his client to sign a certificate of provenance when Miller wanted to sell the Duke to pay medical bills two years earlier. Hassan clearly stated: "Garry wouldn't like it if you spoke to Jose about the ball." Why? "Because she's been ill recently and it would only upset her."

Intrigue turned into suspicion when I read an Independent on Sunday article written three weeks after the sale. Under the headline "Howzat for a mystery: did Garry Sobers hit it for six sixes – or is £26,000 ball an imposter?", the report questioned the Duke's authenticity because of its make.

I later learned that the Christie's lot notes had claimed Glamorgan were being supplied with Duke balls during the 1960s and the sold one was the last of three used in the over – the first two sixes having been hit out of the ground and "allegedly returned to the umpires". Not so, according to the bowler, Malcolm Nash, who I rang in Kansas, where he was working as a cricket coach. He was adamant: he had bowled one ball and cited BBC Wales footage of the feat showing it being returned to him after every six except the last one.

Nash also confirmed that Glamorgan had used only Surridge balls supplied by the club's scorer, Bill Edwards, through his sports shop near St Helen's, while the former England and Glamorgan all-rounder Peter Walker told me that his pre-auction protestations had been ignored by Christie's.

I then had a strange conversation with Glamorgan's scorer and archivist, Dr Andrew Hignell, who had been invited to London by Christie's before the auction. After revealing details of that meeting, he refused to let me include any of them in Six of the Best – apart from his being shown the ball and verifying the match details.

When I read a 1968 Glamorgan members' newsletter which confirmed the actual Six Sixes ball had been made "at the firm of Stuart Surridge, the former Surrey captain", I knew the Christie's Duke was a wrong 'un – something I had hinted at with a heavy heart in Six of the Best because Sobers had been a boyhood hero of mine.

And that was that until May 2012 when the disputed Duke popped up for sale at Bonhams in Chester. As I continued looking for more evidence, I made the most startling discovery of all: while being filmed at St Helen's six months before the 2006 Christie's sale, Sobers had admitted that one ball had been used in the over and not three.

I established that the Bonhams lot entry relied heavily on the questionable Christie's catalogue notes, and after being fobbed off by Bonhams' sports memorabilia department, I threatened to go public with my evidence and was immediately invited to Chester. The saleroom director, Alexander Clement, spent an hour examining my material and promptly withdrew the ball because of my "compelling and conclusive" evidence.

My strategy was straightforward: I hoped to persuade whoever had consigned the ball to Bonhams to return it to Britain. Then, along with my evidence, I could take it to Christie's with Bernard Shapero, the London antiquarian book dealer who had originally bought it in 2006, and try to obtain a refund of the £26,400. Some of those under investigation ran for cover, others were downright unhelpful. But through the honesty of a handful of key players, I began to unravel the riddle.

A solar energy expert based in Faridabad near Delhi, Ashish Singhal, was revealed as the person who had sent the ball to Bonhams and I finally discovered it had been originally bought at Christie's, via Shapero, by the Indian art impresario, NevilleTuli. The worldwide economic downturn meant Tuli had not been able to pay the statutory customs duty and the ball had been bought by Singhal through an airport online auction. He then unsuccessfully tried to sell it back to Tuli.

Following my abortive attempt to bring the ball back from India, I began to focus on the nine people involved in the 2006 sale: Sobers, Miller, Hassan, four current or former Christie's employees and the Glamorgan and Nottinghamshire archivists.

Speaking from Barbados, Sobers said he had made nothing from the sale and recalled signing the ball's certificate of provenance after questioning Miller. "I'm a very innocent bystander because this ball was brought to me nearly 38 years after the event," he said. "I didn't look at the make and even if I had done, I wouldn't remember what it was – impossible! I did what an honest human being would do for a person in trouble."

Miller steadfastly insisted she had nothing to hide. In 1975, she had put the ball in a make-up drawer until a "clean room" extension to her home was needed because of her worsening oesophagus condition in 2006. Miller identified Max Dunbar, the current chief executive of the Manchester Jewish Museum, as the Christie's specialist who had handled the sale and said she had asked Hassan to ring Christie's to vouch for her. After the auctioneers had deducted their 10 per cent, she received a cheque from them and a phone call from Hassan asking for payment. She gave him £3,763.15 – 20 per cent of her net total.

Hassan acknowledged his key role in the certificate's signing but denied contacting Christie's or having anything to do with the erroneous lot notes. After repeated denials, he eventually admitted receiving, but not requesting, a cheque for nearly £4,000 from Miller, "like a commission". Hassan said Sobers didn't know about the arrangement and had been paid nothing because "he said he didn't want any money from it".

Nottinghamshire's archivist, Peter Wynne-Thomas, recalled discussing the impending sale with Andrew Hignell before Glamorgan's archivist went to Christie's in 2006: "I think we talked about whether one or more balls had been used in the over. I'm sure the make of the ball wasn't mentioned."

Having discussed his Christie's meeting with me again – this time without restrictions – Hignell produced a curious catalogue of reasons for not being able to help my investigation, including a Six Sixes file containing no mention of any Christie's contacts, some deleted emails and a lost diary. After eventually agreeing to answer my questions, he later decided not to, after taking legal advice.

The three Christie's specialists proved almost as elusive. Current head of sale Rupert Neelands referred me to their communications director, Matthew Paton, and Max Dunbar said he didn't want to discuss something that had happened six years ago before referring me to Paton and to David Convery, the head of Christie's' sporting memorabilia department in 2006. Convery had already implicated Dunbar by email and when I rang his Convery Auctions office at Blackburn near Edinburgh, he stressed that he had not been involved in the ball's sale. What about the author of the lot notes – was it Dunbar or Neelands? "It wasn't me who wrote them," he replied, and then hung up.

Christie's refused to meet me but their dispute resolution department reviewed my evidence during a re-investigation of the sale. Finally a statement citing the ball's "good provenance" and the certificate signed by Sobers was issued. They had not "found evidence or knowledge of any wrongdoing that helps to shed any light on the subsequent controversy." So the Duke was still the real deal.

While Nash now wants his role to be accurately acknowledged by Christie's – "The ball was charred, scarred and scuffed but never changed and I'd like to see a conclusion to all this nonsense" – I'm disappointed that the unwritten 43rd Law of Cricket covering the exercise of common sense has been ignored. An opportunity to do the decent thing has been passed up – although Miller and Hassan have both indicated their willingness to return their £18,800.

The sale of that scruffy red cherry in 2006 was clearly "just not cricket". Conspiracy or cock-up or a mixture of both? Probably a perfect call for DRS...

The 'other' Six Sixes ball ends up in West Indies

So what happened to the actual Surridge ball that was hit all over St Helen's by Garry Sobers?

Nobody knows. It may have been inadvertently left in a cricket bag somewhere within Trent Bridge or perhaps it disappeared during the redevelopment of Nottinghamshire's ground.

The 'other' Surridge ball associated with the Six Sixes match – also signed by Sobers - now has pride of place in the Cricket Legends of Barbados Museum in the West Indies.

It was given to schoolboy Richard Lewis as a thank-you present after he'd found the ball actually bowled in the over and returned it to Glamorgan two days later.

When the disputed Duke was withdrawn from a Bonhams sale in May 2012, Lewis, now a semi-retired history and politics teacher in Birmingham, decided to consign his Surridge to a Derbyshire auction.

Cricket fan and part-time antiques collector, Chris Davies, from Lancaster, paid £1,000 for the ball before selling it, three months later, for £3,000 to the Barbados museum which, according to general manager Michael Lucas, is its "rightful home".

'Howzat? The Six Sixes Ball Mystery' (Celluloid, £14.99) is published tomorrow. It is available from grahameatcelluloid@btinternet.com or 01522 542555

Grahame Lloyd's investigation will be featured on BBC East Midlands' Inside Out at 7.30pm tomorrow