Smith, Marsh hit tons to put India A attack to the sword
Riding on the two batsmen's centuries before both were retired out, Australia made 327 for three wickets by stumps on day one of the match against a largely unimpressive India A attack at the Brabourne Stadium.
At close, Mitchell Marsh (16) and Matthew Wade (7) were the unbeaten batsmen.
Smith and Marsh came together after the visitors had lost openers David Warner (25) and Matt Renshaw (11) when the score was 55 for two. They were largely untroubled by the home team's attack before both retired to the pavilion after notching up hundreds and putting on 156 runs for the third wicket.
Medium pacer Navdeep Saini dismissed Warner and Renshaw in his six-over first spell by coming on as first-change before lunch and then finished with 2 for 27 at the end of the day. Captain Hardik Pandya picked up the wicket of Peter Handscomb late in the day with the second new ball.
Smith, who is expected to be a big thorn in the Indian bowlers' flesh in the four-Test series commencing at Pune on February 23, played fluently against both pace and spin.
The right-handed batsman made 107, his 30th hundred that includes 15 in Test cricket in his 100th first-class game, in 161 balls before he decided not to resume his innings after tea, when Australia were 211 for 2.
Smith played a chance-less knock and impressed with the way he dealt with left-arm spinner Shahbaz Nadeem. He also smacked him over long on for a six by dancing down the pitch besides timing the ball superbly to hit 12 fours too.
The left-handed Marsh, preferred over Usman Khawaja repaid the faith by making an assured 104 in 173 balls and in 213 minutes.
He too retired after reaching his century after tea to leave Peter Handscomb (45) and his brother Mitchell Marsh (16) to carry on when the total read 288 for two in 75 overs.
Shaun, who struck 10 fours and one six, could have been out on 88 when he pulled part-time spinner Akhil Herwadkar but was put down by Saini at short mid-wicket.
The home team's bowling suffered a setback when off-spinner Krishnappa Gowtham hurt his hamstring while fielding after lunch and limped off the field.
Saini, who took 2 for 13 in his pre-lunch spell of six overs, too limped off after bowling four balls in the first over after lunch but returned to the field and also bowled a couple of overs late in the day.
In the morning, India A started well when Warner and Renshaw were both dismissed by first change Delhi medium pacer Saini before the visitors recovered through the 156-run stand between Smith and Marsh in 40.5 overs.
Smith arrived at the crease at the fall of his deputy Warner in the 9th over of the innings. He batted fluently and was hardly troubled by the bowling barring once when he edged left-arm spinner Nadeem short of the slip fielder when on 55.
He completed his century in 154 balls with the help of 11 fours and a six in 186 minutes.
Marsh took a cue from his captain and began to play with increased confidence to complete his half century in 86 balls and 131 minutes.
The third-wicket duo completed the century stand in 41.1 overs and looked well in control against a none-too-impressive bowling attack on a pitch that had eased out considerably in the afternoon session.
In the morning, Australia lost both their openers - Warner and the tall England-born Renshaw - after they were put in to bat by Pandya.
Dinda gave way to Saini after a four-over first spell and the Delhi medium pacer struck a blow in his very first over by packing off pocket dynamo Warner with a short ball that the left-hander tried to pull and got a top-edge to be caught behind by Ishan Kishan.
Warner's 25 came off 43 balls and he hit the ball to the fence on four occasions in his 40-minute essay.
Saini struck again in the fifth over after the drinks break by dismissing the stone-walling Renshaw with a ball that moved away a shade.
Renshaw had occupied the crease for 84 minutes and struck a lone four in his 41-ball knock and at his dismissal the visitors were 55 for two.
The visitors retired out Smith and Shaun Marsh in the second session before Handscomb was dismissed by Pandya in the last session.