The home team was eliminated with a paltry total of 116 by India blew the target away in the 17th over with eight wickets in hand.
Proteas captain Aiden Markram won the toss and chose to bat first in difficult conditions and soon found himself in trouble as Indian seamers Arshdeep Singh (5-37) and Avesh Khan (4-27) wreaked havoc.
Duminy has been in charge of the Proteas batsmen in the white-ball formats since February and has seen inconsistent performances, especially in ODIs.
In the World Cup in India, the Proteas broke the record for the highest ever total in the tournament while also being bowled out for 83 against the host nation and then 212 in the semi-final.
Speaking after the loss to Wanderers, Dominy said: “When you’re trying to build a brand and a style of play, you’re likely to have these contradictory experiences.
“This is where the learning happens. Part of how to find consistency is to actually experience either or and then understand why things happen.”
“That’s the journey for us. When it’s good, we’re really good. When the conditions are good, we can score 400 runs but how can we find our way to 280 off a tough wicket? That’s the question for us.”
Dominy also defended Markram’s decision to bat first in the bullring, noting that the batters had not executed in difficult conditions.
“You make decisions based on the information you have,” he added. “Historically, you think if you go through the new-ball period, it will be a good place to bat and score a good score, from where there is a tendency to spin and the pitch becomes slower.
“It means the chase gets tougher, but they ended up batting in the best part of the day, which was the back of the first innings.
“I don’t think we made a wrong decision, but that was the information we had and we made the decision. When we don’t execute, those questions will be asked.”
“For us, it’s about understanding the choice of intent, and where we can think about that and where we can be better.”
The Proteas have a chance to right their wrongs in the second ODI of the three-match series at Gqeberha on Tuesday.
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