SYDNEY : Usman Khawaja continued his love affair with the Sydney Cricket Ground with a sparkling century as Australia moved to a commanding 266 for two at lunch on day two of the third test against South Africa on Thursday.Khawaja reignited his test career with twin hundreds against England in last year's New Year's test at the venue and brought up his 13th career ton late in the session in an unbroken partnership of 119 runs with number four Steve Smith.Khawaja was 108 not out, with Smith on 59, and the Proteas' hopes of a face-saving win fading through the wicketless session.The match is a dead rubber after Australia sealed the series with wins in Melbourne and Brisbane, but Pat Cummins's side can book their place in the World Test Championship final with another victory.With play abandoned early on day one due to rain, the pair resumed on 147 for two but only three overs were bowled in the extended session before the rain came again to halt play for about 16 minutes.After the restart, Khawaja and Smith comfortably saw off pace duo Kagiso Rabada and Anrich Nortje before hitting out against the spinners as blue skies returned over the stadium.Khawaja danced down the wicket and whacked spinner Keshav Maharaj for six over his head and later pulled Rabada for two to bring up his century.The third-highest scorer in 2022 with 1,080 runs, Khawaja celebrated with a David Warner-style leap and a punch in the air, then danced a little jig with his helmet off.Smith brought up his fifty from 95 balls, working a single off spinner Simon Harmer past square leg in the following over, before easing through to lunch with Khawaja.