Watson again eyeing maiden Test century

Shane Watson and Michael Clarke put Australia's hopes of a crushing Boxing Day Test victory at the MCG back on track after the top order was rocked by Pakistan's twin pace pairing of Mohammad Aamer and Mohammad Asif in the final session on Day Three on Monday.

Within the first 12 overs of the second innings, Ricky Ponting (12) and Michael Hussey (four) succumbed to 17-year-old firebrand Aamer (two for 43), and opener Simon Katich (two) fell to Asif (one for 16).

But Watson (64 not out), who scored his seventh half-century in 12 innings this year, and Clarke's circumspect unbeaten knock of 21 off 65 balls guided the hosts to 111 for three - and a huge lead of 307 - at stumps.

The pair have compiled an unbeaten 71-run fourth-wicket union with Watson the more aggressive of the two, hitting seven boundaries and a towering six of Saeed Ajmal that was lofted high and hard over the long-on boundary.

Pakistan's innings came to a close at tea on 258, in response to Australia's first dig of 454 for five declared, after Doug Bollinger (three for 50) snared three wickets in four overs with the second new ball.

Ponting took the second new ball as soon as it became available and Bollinger re-entered the attack with immediate results as he dismissed nightwatchman Aamer (15), Kamran Akmal (12) and Abdur Rauf (three).

Of the visitors' bowlers, Aamer left the biggest imprint on Australia's second innings.