Australia's mammoth total a new MCG record

Australia have broken the record for the highest total in a Test innings at the MCG, declaring on day five against Pakistan at 8-624.

Australia have broken the record for the highest total in a Test innings at the MCG. (AAP)

Australia have recorded the highest total ever in an Test innings at the MCG, declaring on day five of the Boxing Day Test against Pakistan at 8-624.

Captain Steve Smith made 165 not out while Mitchell Starc's seven sixes in his quickfire 84 were the most ever in an MCG Test innings.

The massive total comfortably exceeded the previous MCG record of 604 made by Australia against England in 1937.

It is the sixth occasion since 2000 that a team has scored 500 or more runs in an MCG Test, with England the only visitors to do so.

The hosts lead Pakistan by 175 runs at lunch in a match that is still most likely to end in a draw, despite Josh Hazlewood striking early in Pakistan's second dig to remove opener Sami Aslam.

HIGHEST MCG TEST INNINGS TOTALS SINCE 2000

* 8(dec)-624, Australia v Pakistan, 2016

* 558, Australia v India, 2003

* 3(dec)-551, Australia v West Indies, 2015

* 6(dec)-551, Australia v England, 2002

* 530, Australia v India, 2014

* 513, England v Australia, 2010