Aussie tail too much for India: Smith

India had no answers to an Australian tail that didn't just wag – it walloped!

After needing all of Friday's opening day to reach 5-259 in the Boxing Day Test, the hosts took just two sessions on Saturday to more than double their score.

And while that underlines just how severely India struggled on day two at the MCG, it is also more kudos for the ever-improving Australian ‘tail’.

"They were terrific. They've come out and taken the bowlers on," centurion Steve Smith said of the key partnerships he formed with Mitchell Johnson, Ryan Harris and Nathan Lyon.

"I don't think they (India) really had an answer for the way they were playing. It's great for us that the tail can come out and do that and be really aggressive."

The tailenders, having rescued the home side time and again during last year's home Ashes whitewash, are proving a massive asset again this summer.

India could well have come into this third Commonwealth Bank Test with the series squared at 1-1.

The tourists scored 408 in the first innings of the second Test at the Gabba and had Australia struggling at 6-247.

But as Smith scored another century, Mitchell Johnson and Mitchell Starc posted invaluable half-tons.

Australia rallied to make 505 and went on to win by four wickets.

Similarly, India did well on Boxing Day.

In-form opener David Warner went for a second-over duck and India never let Australia take the initiative.

All that changed on day two.

Last summer's hero Brad Haddin returned to form with 55 and joined with Smith to put on 110 for the sixth wicket.

Johnson again chipped in with 28, but it was fellow paceman Ryan Harris who starred.

Harris’s highest Test score of 74 included some outstanding shots and formed the bulk of a stirring 110-run stand with Smith.

"We call him Jacques Kallis," injured Australia captain Michael Clarke joked during his role as a guest commentator with the Nine Network.

"He bats more in the nets than any other batsman.

"He thinks he's a batsman."