Hashim Amla has made himself available for consideration for the job of South Africa's next Test captain. ESPNcricinfo understands Amla, who gave up the vice-captaincy of the limited-overs teams in February last year, has had a change of heart about leadership and has informed the selection panel that he can be considered for the role.

That brings to four the number of candidates who will be considered to replace Graeme Smith, who retired in March. While AB de Villiers, who announced his readiness to lead in an interview last week, and Faf du Plessis are considered front-runners for the job, with JP Duminy being talked about as an outside possibility, Amla's interest in the role adds a new dimension to the debate because he has been spoken about as a preferred choice in the past.

Amla was picked as de Villiers' deputy in the shorter formats of the game in July 2011. He ended up leading South Africa in what should have been de Villiers' first series in charge in October that year - against Australia - because de Villiers was injured. He also led a South African XI in an unofficial tri-series in Zimbabwe in June 2012, in which South Africa lost to both the Zimbabwean and Bangladesh sides.

But Amla's reluctance to accept the position was obvious when he chose not to stand in for de Villiers in the 2012-13 season. De Villiers asked for a break from the T20s against New Zealand in December 2012 and was suspended for slow over-rates in the ODI series that followed. Du Plessis took over on both occasions.

At the time, Amla was frank about his feelings on captaincy. "There is no point me being vice-captain if I am not going to captain when the captain isn't around," he said in January last year . Amla also asked for a sabbatical from T20 cricket for the remainder of 2013.

However, when the new season began at the end of 2013, Amla changed his decision on T20 participation and agreed to play in a series against Pakistan. He opened the batting with Quinton de Kock and was seen as being a foil to the explosive young batsman at the other end. Amla was also part of South Africa's World Twenty20 campaign where, although he was criticised for having a slow strike rate, he finished the tournament as their second-highest run-scorer, and only JP Duminy and AB de Villiers scored quicker than Amla among batsmen who played all games.

It has since emerged T20 cricket is not the only thing Amla has changed his mind about. He has also decided he is not as averse to captaincy as he first was - news which, a source close to the situation said, has made the selectors' jobs a lot more difficult. Despite Amla's soft-spoken nature, he is seen as an automatic choice for leader because of his experience in the international game, which du Plessis does not have, and the fact that he is not overburdened by other responsibilities, which de Villiers, who is also South Africa's wicket-keeper is. Amla has also captained in the past, which Duminy has not.

He led South Africa's Under-19 side in the 2002 World Cup and ended up as the third highest run-getter in the team with an average of 27.28. He also captained his domestic side, the Dolphins, ten years ago, in the 2004-05 season and although he asked to be relieved of his duties at the end of that summer, he also 1,000 first-class runs for the first time and scored his first double-century. Then, Amla was just 22 years old and said he believed he needed more time to work on his own batting.

Now, he has had that time. Amla is regarded as one of South Africa's most important batsmen in all formats, a role that will be enhanced in the absence of both Smith and Jaques Kallis. According to insiders, Amla has also been more vocal in the dressing room and added to the think-tank in the field which has made him seem ready to take over as captain.

South Africa's selection panel will make their recommendation for the next Test captain to Cricket South Africa's board at their meeting on June 3. The board will then have to either reject or ratify that choice. The new captain's first assignment is a two-Test series in Sri Lanka in July followed by a one-off Test against Zimbabwe in August.