"The T20 World Cup is in Australia and that's not too far away, so hopefully we'll be back for that and that will probably be my last international tour I would think," du Plessis was quoted as saying by Cricket Australia.
du Plessis felt that the overdose of domestic T20 leagues have made it difficult to pit the best national teams in series other than the World T20, which he felt must be looked at by the International Cricket Council (ICC).
"And I can see the same with other teams -- it's almost never their strongest teams, and fans come to watch the best players play. That's where I see the game moving forward, but the T20 World Cup in 2020 is something I'm really looking forward to -- that will probably be the last tournament for me," he said.
After wrapping up their ODI fixtures with a 2-1 verdict in favour of the tourists, du Plessis' side will face the Aussies in an one-off T20I on the Gold Coast on Saturday.
After asking Delhi to bat first, Chennai bowlers put up a superb show to restrict the first time semi-finalists to 147/9.
Chasing a modest 148 for victory, openers du Plessis (50; 39 balls; 7x4; 1x6) and Watson (50; 32 balls 3x4; 4x6) were off to a slow start but recovered in time to share a 81-run stand for the opening wicket.
South Africa captain du Plessis was the aggressor early on and once he got out, Watson took over as Delhi bowlers looked hapless.
Having notched up his his 12th IPL fifty and fourth this season, du Plessis mistimed a pull to Keemo Paul at deep square leg off Trent Boult's bowling while Amit Mishra had Watson caught by Boult at wide long-off.
Suresh Raina (11) was castled by Axar Patel, bringing skipper M.S. Dhoni to the crease. With 21 needed off 24 balls, it was a cakewalk for the defending champions, although Dhoni (9) got out with two runs required for victory.
Dwayne Bravo was at the crease as the yellow army crossed the target with four leg byes with Ambati Rayudu (20 not out) at the other end and an over to spare. Chennai posted 151/4 in 19 overs.
Chennai will now take on old foes Mumbai Indians in the final in Hyderabad on Sunday, the fourth time the two teams will be locking horns in the summit clash.
Earlier, Harbhajan Singh (2/31) and Bravo (2/19) used their reservoir of experience to good affect while Deepak Chahar (2/28) continued his rich form with the ball as Delhi never got going despite having Rishabh Pant at the crease for more than an hour.
Ravindra Jadeja (2/23) and Imran Tahir (1/28), their best bowler this season, also returned impressive figures.
It was an uncharacteristic innings from Pant who was initially starved of the strike and then kept at bay by the Chennai bowlers as the 21-year old eventually managed 38 off 25 with the help of two fours and a six.
Pant looked to be taking off when he hit Tahir for a four and six in the 17th over which yielded 14 runs. But Bravo bowled a brilliant 18th over in which he gave away just three runs besides accounting for Keemo Paul (3).
Chahar dismissed Pant in the penultimate over with Bravo taking the catch at long-on before Trent Boult (6 off 3) and Ishant Sharma (10 not out off 3) smashed some lusty blows to take the score close to the 150-run mark.
It all started with Chahar trapping young Prithvi Shaw (5) in front in the third over.
Harbhajan then accounted for the in-form Shikhar Dhawan (18), the India southpaw giving a healthy edge to Dhoni who took the catch in his second attempt.
Colin Munro and Shreyas Iyer then tried to steady the ship but just when the former was looking good, Ravindra Jadeja had him caught at deep square-leg by Bravo for 27 off 24 deliveries.
Iyer (13) departed soon after, skying a Tahir googly to backward point where Raina completed a good catch. Axar (3) too failed to contribute, holing out to Tahir at third man off Bravo's bowling.
Harbhajan then sent back Sherfane Rutherford (10) and it all looked downhill from there for the first time qualifiers.
Brief scores: Delhi Capitals: 147/9 in 20 overs (Rishabh Pant 38; Deepak Chahar 2/28, Harbhajan Singh 2/31, Ravindra Jadeja 2/23, Dwayne Bravo 2/19); Chennai Super Kings: 151/4 (Faf du Plessis 50, Shane Watson 50)
"We spoke about it before the game - didn't have the best run in the last 5-6 games," said man of the match Du Plessis in the post-match presentation ceremony. "We have a lot of confidence as a team to win a lot of big games - so we draw confidence from that. We also know the strength of ours is getting those partnerships - even if we go 3-4 overs without runs, we have a great lower and middle order to bring us back.
"Watto (Watson) thanked me already for scoring quickly at the beginning before he got set. Hopefully we can both get them off the meat in the final right from the word go," said Du Plessis.
Watson admitted that he was nervous in the beginning. "Very grateful for the faith CSK have shown in not just me, but all the players are grateful. Faf batted beautifully. Thanks to Faf for helping me through that stage," said the 37-year-old former Australian captain.
"There are huge positives about age and experience. We have played well from the top with MS (Dhoni) and Fleming. When you have experienced players, you have an understanding of what to do. We are making the most of the experience we have had and we are going to make the most out of it on Sunday," he said.
The pair survived a comical mix-up early in the innings. Watson tapped the ball to point and Du Plessis set off before the former started stuttering. Both batsmen ran together in both directions at one point while the DC fielders threw at both the stumps and missed. In the end, the pair ran a single.
"I reckon we almost ran three there," said Du Plessis. "It was terrible running, and that's not the kind of start you want in a run-chase of a knockout. Thankfully we recovered from that and did pretty well."
The Proteas ended up losing 3-0 in India and were hardly able to give a fight to the hosts at any point in the series.
"Every Test match they bat first, they score 500, they declare when it's dark, they get three wickets when it's dark and when day three starts you are under pressure. It was like copy and paste in every Test match," Du Plessis is quoted as saying on ESPNCricinfo.
"(If the toss is removed) then away teams will have a better chance. In South Africa I don't mind that, we bat on green tops anyway."
The comment has not gone down well with many Indian fans who think that it was nothing more than an excuse.
"And if you thought Faf du Plessis was done with giving horrible excuses, you're wrong. This guy won't stop. Lmao. Ridiculous #INDvSA," a fan wrote.
"Look, if the captain of the side has this mentality, the team can never bounce back. NEVER. You saw that in the World Cup. You saw the same in the Test series in India. Faf needed to do what Kohli did to India in SA after 2 Tests, not what he did here," another fan said.
There were some who held back because of the fact that Du Plessis is also a Chennai Super Kings player. "Want to take a dig at Faf du Plessis but the CSK fan in me holding me back," said one such fan.
"This man simply don't know how to accept the defeat," another fan wrote.
Some pointed out that the pitches during the series were closer to what the Proteas would have found in South Africa. "He's doing a disservice to himself, his stature and post, and his team, with these comments. Bavuma said that Pune was like a SAF wkt, and they had full use of it. And yet, their bowlers kept bowling crap until India declared. Why not accept your own shortcomings first?"
Du Plessis, however, also pointed out that South Africa's woes don't have any quick fixes. This series follows a dismal performance in the World Cup in which South Africa won just three out of nine matches and failed to make it past the group stage.
Faf du Plessis wants to get rid of the toss in away Tests
? https://t.co/6AE7XLGJg3 pic.twitter.com/pH1IUohRj9
— ESPNcricinfo (@ESPNcricinfo) October 26, 2019
"It has been an honour to play for my country in all the formats of the game, but the time has come for me to retire from Test cricket. If someone had told me 15 years ago, that I would play 69 Test matches for South Africa and captained the side, I wouldn't have believed them. I stand in a place of utmost gratitude for a Test career full of blessings bestowed on me," the 36-year-old wrote in his statement.
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"The next two years are the ICC T20 World Cup years. Because of this, my focus is shifting to this format and I want to play as much of it as possible around the world so I can be the best player I can possibly be. I strongly believe that I have a lot to offer to the Proteas in this format," he said.
He also clarified that he is not retiring from ODI cricket yet. "This does not mean that ODI cricket is longer in the plans,. I'm just making T20 cricket the priority in the short term," he said.
du Plessis made his Test debut in November 2012 against Australia in Adelaide. He went on to score 4,163 runs in 69 Tests at an average of 46.32 with 21 half-centuries and 10 centuries. He also captained South Africa in 36 Tests between 2016 and 2020 with 18 wins, 15 losses and three draws.