The 27-year-old Delhi left-hander blasted a 150-ball-248, which is only the second highest individual List A score behind former Surrey batsman Alistair Brown's 268 against Glamorgan at the Oval, back on July 19, 2002. (Agencies)
Riding on Dhawan's brilliance and some solid support from skipper Cheteshwar Pujara (109 not out), India A amassed a mammoth 433 for three in 50 overs.
The target was a tall-order for the home team but their batsmen fought hard before being bowled out for 394 in 48.4 overs.
Reeza Hendricks (102, 78 balls, 12x4, 2x6) and Vaughn van Jaarsveld's (108, 91 balls, 7x4, 5x6) centuries were not good enough to take the hosts past the finishing line.
India A will meet Australia A in the final on Wednesday. The day undoubtedly belonged to Dhawan, who hit 30 boundaries and seven sixes in his innings during which he surpassed Sachin Tendulkar's 200 not out against South Africa in 2010 at Gwalior and Virender Sehwag's 219 against West Indies in Indore back in 2011.
If Dhawan's first 100 came off only 86 balls, the second hundred came off only 46 balls as he raced to his maiden List A double hundred in only 132 balls with a push off left-arm seamer Beuran Hendricks' bowling at the LC de Villiers Oval.
Just when it looked that he would eclipse the world record, he was caught by wicketkeeper Dane Vilas of Rusty Theron's bowling trying another slog shot.
Such was his domination that out of his 162 out of his 248 runs came in only 37 scoring strokes.
Dhawan added 285 runs in only 33.5 overs with his skipper Pujara, who also helped himself to a three-figure mark having faced 97 balls and hit eight boundaries.
The 27-year-old Delhi left-hander blasted a 150-ball-248, which is only the second highest individual List A score behind former Surrey batsman Alistair Brown's 268 against Glamorgan at the Oval, back on July 19, 2002.