Captain Steven Smith continued his dream run by notching up his fourth century of the series as Australia piled up a mammoth 572 for seven declared to put themselves firmly in the driver's seat in the fourth and final cricket Test against India here today. The young Australian captain, who has been in stupendous form, scored 117 to record his eighth Test ton and put Australia in a commanding position with useful contributions from Shane Watson (81), Shaun Marsh (73) and Joe Burns (58) on yet another disappointing day for the visitors. In reply, India lost opener Murali Vijay for a nought only to recover and end the second day on 71 for one. The visitors trail by 501 runs with Lokesh Rahul (31 not out) and Rohit Sharma (40 not out) fighting on. Earlier, resuming at the overnight score of 348 for two, the hosts rode on a 196-run third wicket partnership between Smith and Watson to take the attack back to the opposition as Mohammed Shami picked up a five-wicket haul. India though, ably led by Shami (5-112), seemed to have learnt their lessons from the opnening day to concede just 72 runs in 30 overs in the first session of play. Two wickets fell in the morning session and Watson was the first to go when Shami struck for the second time in the innings to deny the No.3 batsman in what would have been a well-deserved hundred. He added only 20 runs to his overnight score. Smith played a defiant knock to post his fourth ton in this series only to be caught behind off Umesh Yadav (1-137) in the 114th over of the innings. But the visitors were once again put to task in the post-lunch when Marsh and Burns managed a 114-run fifth wicket stand to pile on the misery for Virat Kohli and company. Shami once again picked up the all-important wicket of Marsh, the only wicket for India in the post-lunch session, as the left-hander was caught behind after registering his third Test fifty. Shami then came back all guns blazing in the final session to send back Burns after the youngster got his maiden Test fifty in just his second match. Ryan Harris (25) then swung his bat around to hit five boundaries before becoming Shami's fifth strike of the innings. The Indians, understandably, were more sedate in their reply after losing Vijay and Lokesh and Sharma stitched an unbeaten 71-run stand to raise hopes of revival come day three. Rohit and Rahul batted with patience for much of the final session of play, with the 50-mark coming in the 19th over. But there were some nerves towards the end as the bowlers searched for one more breakthrough before end of play. Earlier, Australia had continued their charge towards a high first innings total after tea. Harris, courtesy his 9-ball cameo, helped put up 26 runs for the seventh wicket with Brad Haddin (9 not out) to pile on the misery for India. Shami then dismissed Harris and the innings was declared. Ashwin (1-142) and Yadav were the other wicket-takers for India, while Bhuvneshwar Kumar (0-122) and Suresh Raina (0-53) went wicketless. This was after the Smith and Watson show that put Australia on the road to a big score. Post-lunch, Marsh and Burns looked to heap further misery on the visiting bowling attack and they did just that, putting on 114 runs for the 5th wicket without much fuss. The 450-mark came up for Australia in the 127th over as the two batsmen kept plugging for runs. Marsh brought up his second successive half-century of the series in the 137th over, facing 87 balls. His knock included one six and there were hints of aggression from both batsmen towards the latter half of this second session. The 500-mark thereafter came up in the 143rd over and an over later they brought up their 100-run stand. In the 146th over, when Burns reached his maiden Test fifty off 94 balls, India became the first team to allow four opposition teams with their top six batsmen all scoring half-centuries in the same innings. They got some respite when Marsh was out close to the break, caught behind off Shami. But Haddin came out looking to play his shots, hinting that the declaration may come up shortly in the last session today. Earlier in the day, Smith (82*) and Watson (61*) looked to further frustrate the Indian bowling attack and take forward their 144-run partnership. They were successful to quite some extent as the runs came easy despite the second new ball only ten overs old. They weren't as prolific as the openers on day one morning as Bhuvneshwar and Shami started proceedings. Smith was more comfortable at the crease, continuing his good run of form as Watson looked to graft his way to a big score, crossing the 150-mark in their partnership early in the session. Ten overs into the day then, the 100th of the innings, Smith brought up his 8th Test hundred off 168 balls to a rousing reception from the SCG crowd as he paid tribute to late Phillip Hughes by twirling his bat towards the skies. In doing so, the young captain matched South Africa's Jacques Kallis as the only other player to score four consecutive hundreds in a four-match series. He also matched the feat of Sir Don Bradman who scored four hundreds but in a five-match series. Smith also became the second highest Australian run-scorer in a four-Test series. He fell short by 9 runs of the highest score of 706 runs held by Ricky Ponting, scored against India in 2003-04. The 400-mark came up in the 107th over. And while Smith was garnering all attention for his immense run-scoring, Watson looked to clear the ropes off Shami in the 108th over and only managed to hand out a regulation catch to Ashwin in the deep. Six overs later, it became a double-blow as Yadav had Smith caught behind by Saha, the batsman flashing at a good length ball. It could have been a third quick dismissal had Murali, at short gully, held on to a low, one-handed catch to his right off Ashwin in the 115th over with Marsh (on 9*) the batsman to get a life. The batsman, along with Burns, then avoided any further loss as Suresh Raina (0-53) bowled the last over before lunch. On the opening day, David Warner (101) and Chris Rogers (95) had also laid a solid foundation of a 200-run opening stand to set the hosts for a huge first innings total.