Steve Smith has continued his incredible start as Australia’s 45th Test captain, posting a century at the MCG.

Smith, who earned man-of-the-match honours at the Gabba for scoring 133 in his captaincy debut, once again steadied Australia’s cause.

The 25-year-old resumed on 72 when day two of the Boxing Day Test started in Melbourne.

He reached triple figures in the 101st over, clipping a ball off his pads to fine leg for an 11th four.

Smith removed his helmet and pointed to the sky with his bat in memory of Phillip Hughes, who died last month after being struck by a bouncer.

Smith is in the form of his life, having scored an unbeaten 162 at Adelaide Oval in the first Test when captain Michael Clarke hurt his hamstring and was ruled out of the four-Test series.

“It hasn’t had any negative impact on his batting,” Clarke said of Smith’s promotion, while calling the game for the Nine Network.

“Steve’s loving this extra responsibility, he’s batting beautifully here and it’s been an amazing year for him.”