Steyn had long been on the Stars wish list and he joins fellow South Africans AB de Villiers and Chris Morris in the BBL, after de Villiers signed with the Brisbane Heat and Morris with the Sydney Thunder. Steyn joins Nepal legspinner Sandeep Lamichhane as the Stars' second overseas signing.
The paceman, South Africa's most successful in Tests, retired from the longest format in August following a sequence of injuries, bringing the curtain down on a great career. However, he is still contracted with Cricket South Africa and available for ODI and T20I selection although he was left out of South Africa's recent T20I tour to India with the selectors claiming he was not medically ready, even though Steyn believed he was fit.
The Stars got in contact with him shortly after he announced his Test retirement and, following a short period of negotiation, CSA cleared him to play the first six games of the BBL although Steyn suggested the door remained open for an extension if he doesn't get selected for the England limited-overs series, which starts in early February.
"It's something that I've wanted to do for a while, play Big Bash," Steyn said. "Unfortunately representing the Proteas for the bulk of my career over Christmas time we've always got Test matches on, the Boxing Day and New Year's Test matches. So I haven't been available. But since retiring from Test cricket, it's opened up a little window for me while the Proteas play red-ball cricket."
Steyn hasn't played since he injured his shoulder in the IPL in April and he was ruled out of the World Cup shortly after it began. He is currently preparing to play for Cape Town Blitz in the Mzansi Super League, which begins in November.
He said his body has been in great shape after retiring from Test cricket but that he has found training on his own challenging. "It's been a bit boring," Steyn said. "I'm doing a lot of training by myself and a lot of training with the high school kids. They're the only teams I can kind of practice with right now. So if you ask them, they're pretty scared, but they're surviving.
"The biggest relief off my shoulders was when I retired from Test cricket and I knew I didn't have to bowl 40 overs in a Test anymore. It was amazing. All the training that I'm currently doing right now, it's to bowl only 24 balls. When I put that into comparison to what I've done over the last 15 years of my career it really is pretty easy."
The ten-game home-and-away leg of the Mzansi Super League finishes on December 8. The eliminator is on December 13 and the final on December 16, with Steyn planning on playing every match for the Blitz.
The Stars' first game of the BBL is on December 20, against the Heat at Metricon Stadium on the Gold Coast, and Steyn is expected to be available for that match. However, he will not face de Villiers, who will join the Heat in the second week of January.
Steyn said the pair had been exchanging messages. "It was strange. This was somehow leaked maybe a month ago, it leaked quite quickly and then went quiet and then AB caught wind of it and he sent me a message and said to me he was going over to play but he couldn't tell me which team. But he was excited that we were both going to be in Australia," Steyn said. "I think he was just excited to know that there would be another South African there that he could try and bully around the ground."
Unfortunately, that clash seems unlikely as Steyn's last game for the Stars is set to be the Melbourne derby against the Renegades at the MCG on January 4 and the Stars' second game against the Heat is on January 25.
South Africa's next ODI is February 4 against England with the T20Is starting on February 12 and Steyn is likely to be needed in South Africa prior to prepare for that series if selected. Part of the reason he is playing in the BBL is to get some cricket in Australia ahead of the men's T20 World Cup in October next year.
"It all depends on selection, but right now I am available for South Africa so I have to kind of wait for that selection to happen," Steyn said. "I guess it's maybe one of the reasons why Cricket South Africa has let me go, to be honest.
"I think knowing that I'm not available for the Tests, wanting to keep me fit but also having one eye on the T20 World Cup at the back end of next year I think they probably felt like it was a good call to let me go, which is also great because it keeps me in the running for that World Cup." AGENCIES