Seven batsmen give South Africa X-factor - Kirsten

South Africa's lengthened batting line-up is the driving force behind their ascendance to the world No.1 title and the defence of it, according to coach Gary Kirsten. In their last two series, South Africa played seven frontline batsmen, which Kirsten said gave the team an "X-factor," other countries do not have.

"We can pick a No.7 batter and that has helped us in certain situations. We don't take that combination lightly. We know how important that is to our Test side in terms of the performances that we all want. There might come a time when we need to look at it another way but for now we have that," Kirsten said at the team's arrival in Cape Town.

After Mark Boucher was forced to retire with a severe eye injury ahead of the England tour, AB de Villiers was tasked with the responsibility of wicketkeeping. JP Duminy played as the seventh batsman in England and would have done the same in Australia had a ruptured Achilles' not cut his tour short.

Faf du Plessis replaced Duminy and played an important part in South Africa saving the match in Adelaide and winning in Perth to clinch the series. But, both Duminy and du Plessis have masked the under-performance of South Africa's No. 4. Jacques Rudolph and Dean Elgar have a combined average of 21.5 in that position over the last six Tests.

Rather than focus on the one chink in their armour, Kirsten praised the bench strength for being able to make the step up. "What's important for us is depth. We need to make sure if we have an injury, we have guys who can fill the gap," he said. "I'm encouraged by the players who have come through over the last year."

Since Kirsten took over as the national coach, South Africa have debuted six players and only Dean Elgar and Imran Tahir did not make significant marks on the international stage. Vernon Philander, Marchant de Lange, Rory Kleinveldt and du Plessis have all impressed in varying degrees. Under Kirsten's watch, Robin Peterson has made a successful comeback to Test cricket as well.

For that, Kirsten is impressed. "If we have Robbie there in place of Imran, that's a good thing. To have a person who can play if someone is not in form or gets injured. If we have a Rory in place of one of the seamers; that's also a good thing."

With sufficient depth, Kirsten believes South Africa are readying for an extended stay at the top of the rankings. "It's something that we've set our sights on. It's been an incredible year and it requires time for the players to reflect on that year. We wanted to become the No.1 team in the world and then to hold that position.

"We accomplished two very big targets this year in England and Australia, which is just massive and now we will definitely set our sights on how we can hold that position. It is important to us, this team wants to leave a legacy behind and we are excited by where we are at the moment."

South Africa played nine out of ten Test matches in 2012 away and the home fans have not had the opportunity to see them perform since they rose to the top. Now that the summer has arrived, that will be the chance. Over the course of the next three months, South Africa host New Zealand and Pakistan for five Test matches, three T20s and eight ODIs.

While the Tests will be an opportunity to show off their ranking, the limited-overs matches will form part of a building process. The next World T20 is two years away and the fifty over World Cup three. That will give Kirsten the room he needs to translate the achievements of the Test side to a campaign for ICC silverware.

"It takes time to transfer the success," he said. "In the Test side, we've got some great players and its not to say we can't achieve the same level of success in the one-day side but it takes time. We've got a really good team culture in the Test side and we've certainly tried to do whatever we can in the one-day component to build the same culture but I don't think it will come around as quickly."