'Test captaincy has made me a better player' - du Plessis

'I've been feeling technically sound' - Du Plessis (2:20)

Faf du Plessis credits Test captaincy for his current run of form, including his record-breaking 185 at Newlands against Sri Lanka (2:20)

Faf du Plessis has credited his promotion to the Test captaincy with his current form, which has seen him rack up two hundreds in three innings, including today's record-breaking 185 at Newlands, to complete his most successful summer in ODIs, and it's not over yet.

In 10 matches, du Plessis has scored 640 runs at 71.11, including three hundreds and two fifties, more than other period. South Africa still have one match against Sri Lanka later this week and five in New Zealand later this month, for du Plessis to add to those numbers.

"Being a captain makes me play better. That's possibly been a reason for [my good form] ," du Plessis said after recording the second-highest score by a South African in ODI history.

"The confidence and the momentum of that definitely helps. It just makes you raise your own bar of performance, you want to be a better player. My challenge to myself was to be a good player and now it's to become a great player. So it's just about lifting the bar and making a mind shift."

Du Plessis batted from the second over until the last, when he was caught on the long-on fence while seeking to overhaul Gary Kirsten's 188 not out. He said the record was not on his mind, neither was a first double-century by a South African in ODIs.

"I didn't know about the record. I am very happy that I got to 180," du Plessis said. "The record is something that would have been nice but not for one second did I think of it and 200 was also not on my mind. I was just trying to get as many runs as possible."

Apart from the two century stands that du Plessis shared with Quinton de Kock and AB de Villiers, a hallmark of his innings was strike rotation, particularly with de Villiers. They were together during a six-over period in which Sri Lanka did not give away any boundaries, and they still managed to score 32 runs in the process. South Africa totalled 151 singles and, in a game of small margins, that was one of the differences between them and Sri Lanka - who ran 103. Du Plessis explained it was a deliberate tactic to keep the scoreboard moving.

"That's my game, which is to not give many dot balls. I try and make sure I take pressure off myself by just rotating the strike and running well and, luckily in our team, we've got amazingly quick guys between the wickets and we've put a lot of pressure on the opposition," he said. "Our ones and twos stats right through the series have been incredible - we've got two or three times the number of the Sri Lankans. That is so difficult to bowl to - when you get guys that continuously run you off your feet."

Interestingly, the partner with whom du Plessis' enjoyed the most success in singles and overall terms was de Villiers, whom he succeeded as Test captain and whom he plays under in ODIs. The pair are childhood friends and, although du Plessis appears to have taken to the captaincy quicker than de Villiers did, he does not mind being relegated to working under someone else for a change. "Since AB has come back, we've worked really well together. I can feel that on the field we talk from the same mouth almost," du Plessis said.

What they will both be saying for the next few days is that a whitewash over Sri Lanka is their main goal. Not only will it see them overtake Australia at the top of the rankings but it will also prove their ability to win consistently, which South Africa insist will be crucial when it comes to major tournaments.

"Five-nil is important now to get to No. 1. For a while we have targeted to get back at the top in all formats, and we are getting there very quickly. Five-nil would be a great achievement, no matter who you play against."

As hard as Sri Lanka fought in the fourth ODI, they have not given South Africa as much of a challenge as they would have liked, except during the T20s against an experimental host outfit. Still, du Plessis was happy with South Africa's ruthlessness, although he would like to see their attack engage in more contests like the one they had on Tuesday night.

"You have to beat who is in front of you and you have to do it well and I think that's something we have done very well," he said. "Our skills have been very good right through the series. We haven't taken our foot off the gas.

"From a bowling point of view, yes, Sri Lanka's team are possibly not the best batting line-up in the world, but we're still doing what's required. Today was a pressure situation, we know that they are very top-heavy and score runs up front, and the bowlers possibly didn't start as well as they would have liked but they came back.

"It's important that we get pushed. Especially with a young bowling unit, we want to get those bowlers in some pressurised moments because that's what big games are all about. That's the difference between winning tournaments and not - the pressure."