‘The biggest signing in the history of the Big Bash’

A heartfelt email from Darren Lehmann helped the Brisbane Heat land the signature of AB de Villiers, who Chris Lynn has labelled the "biggest signing in the history of the BBL".

A courtship two-and-a-half years in the making was confirmed on Tuesday, with Lynn suggesting "Christmas has come early" with one of the most talented cricketers the game has ever seen to make his KFC Big Bash debut during the second half of the coming season.

De Villiers, who retired from international cricket following the controversy-laden Test campaign against Australia last year, has hardly spent a Christmas at home in Pretoria since his entrance to the top flight over 15 years ago.

A key mantra of Lehmann's five-year tenure as Australia's head coach, which incidentally also ended after that tour of South Africa, was that family should always come before cricket.

That, according to Lynn, was a major factor in clinching a commitment from de Villiers to play for the Heat after the batting maestro had spurned initial interest from numerous clubs and appeared unlikely to feature in the T20 tournament.

"'Boof' actually wrote him a nice lengthy email saying, 'No issues if you don't want to come, it's all good, you have to take care of your family," Lynn said in Brisbane on Tuesday.

"'Christmas time is all about family and friends and enjoying yourself.' It was something that might have got him over the line.

"Having known AB, you don’t want to keep poking the bear. We wanted to sign him, every club wanted to sign him, the BBL wanted to sign him… The fact we didn't chase him every day (was helpful)."

Some have suggested the BBL has lacked star power in recent seasons, but few would disagree with Lynn's call that de Villiers represents the biggest fish the eight-year-old competition has ever reeled in.

And, while he's been out of the international game for nearly 18 months, the 35-year-old is far from over the hill.

He hit 348 runs at 70 in eight hits for Middlesex with an astronomical strike-rate of 182.19 in England’s recently concluded domestic T20 competition, while he was typically explosive for Royal Challengers Bangalore in the Indian Premier League earlier this year (442 runs at 44, strike-rate of 154.00, from 13 innings) to justify his $A2.2 million contract.

"We want him to play as many games as he can, but we're really understanding that Christmas and New Year's is really special to spend at home when you've been playing international cricket for so many years," said Lehmann, who expects de Villiers to be available sometime in early January.

"He wants to play in the best competitions, he wants to play the best cricket he can. He's a cricket 'nuffie', which is great.

"He's going to be fantastic for our young guys. He loves playing the game, he's just passionate… Hopefully he stays on for years to come."

Lynn notes de Villiers' skill against spin bowling, the influence of which has grown in recent seasons of the BBL with the likes of Rashid Khan, Sandeep Lamichhane and the Heat's own Mujeeb ur Rahman among the most effective bowlers, will be an important point of difference to local Australian batsmen.

The South African will come in for Brendon McCullum, who called time on his BBL career last summer, though Lehmann says they haven’t yet decided where to bat their new recruit.

"What he's going to bring to not only to Brisbane, but the competition as well, is the next level (of talent) that we've been chasing for a number of years," said Lynn.

"With Brendon retiring it's basically a clean swap with AB and we're looking forward to not only what he can do on the field, we're just looking for another experienced champion the change room."

Lynn and McCullum had been the BBL's biggest attraction in recent summers, wearing the 'Bash Brothers' moniker with pride and fiercely refusing to adopt any further siblings into their club of two.

Now, Lynn admits, that has all changed: "The fact he's one of my heroes means he can have a free pass into the Bash Brothers."