Close South Africa A 301 (Cullinan 86, Amla 81, Lee 4-37) and 232 (Kemp 56, MacGill 4-114) lost to Australians 574 for 9 dec (Langer 161, Lehmann 60, M Waugh 110, Watson 100*, Gilchrist 56, Pretorius 5-148) by an innings and 41 runs The Australians continued their juggernaut progress when they beat South Africa A by an innings and 41 runs with a day to spare at St George's Park on Sunday.

Shane Watson hammered a century off 97 balls in his first match in the national colours as the Australians took a 273-run first-innings lead before declaring on the third morning of the scheduled four-day match.

South Africa A lost their top five batsmen between lunch and tea before being bowled out for 232. Their only highlight was a hard-hitting seventh-wicket stand of 87 in 75 minutes between Justin Kemp (56) and Goolam Bodi (45).

Steve Waugh, the Australian captain, declared as soon as Watson reached his century on the third day of the four-day game. The Australians had made 574 for 9 declared in reply to South Africa A's 301 all out.

Watson faced only 67 balls as he took his overnight score of 20 to 100 not out, and faced 97 balls in all. He hit 14 fours and three sixes, and reached his second first-class century with a pulled six off Goolam Bodi, the left-arm spinner.

Watson, a 20-year-old allrounder from Tasmania, was included in the Australian party for the South African tour to gain experience. He remains unlikely to play in the two remaining Test matches, despite making full use of what is likely to be his only opportunity to play in a first-class match on the tour.

When South Africa A batted again, openers Graeme Smith and Jacques Rudolph put on 31 before Rudolph was caught behind off Brett Lee in the fifth over after lunch.

Stuart MacGill then dismissed Smith and Martin van Jaarsveld in successive overs, before fast bowler Andy Bichel claimed the wickets of Hashim Amla and skipper Daryll Cullinan - the first-innings top-scorers - which effectively ended the A team's challenge.

Watson chipped in with the wicket of Robin Peterson in the first over after tea. Justin Kemp and Bodi delayed the Australian victory with some aggressive strokeplay before they were out in the space of eight balls. Kemp made 56 off 72 balls with seven fours and a six, while Bodi hit 45 off 70 balls with five fours and a six.

Australia, who won the first Test in Johannesburg by a record margin of an innings and 360 runs, play South Africa in the second Test at Newlands in Cape Town, starting on Friday, March 8.

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