(CNN) -- Pakistan finished top of Group A after inflicting Australia's first defeat in 35 matches at the Cricket World Cup on Saturday, a run which has seen Ricky Ponting's team win the title three times since 1999.
It was the veteran Ponting's first reverse in 28 World Cup matches as captain, and means his team will likely face fellow heavyweights India or England in the quarterfinals after finishing third in the seven-nation pool.
Pakistan's reward for the four-wicket victory in Colombo is a likely clash with the West Indies or England.
The last-eight scenario will be known on Sunday after India take on the Windies -- England have already played all their round-robin fixtures.
Pakistan went into the match against Australia in fourth place, a point behind New Zealand -- who will now play Group B winners South Africa following the Proteas' 206-run thrashing of co-hosts Bangladesh earlier on Saturday.
Australia, seeking a fifth title in the 10th staging of the 50-over tournament, posted a poor total of 176 all out -- the team's lowest at a World Cup since 1992 -- as Pakistan's opening bowler Umar Gul took 3-30 and all-rounder Abdul Razzaq chipped in with 2-8.
Opener Brad Haddin top-scored with 42 while vice-captain Michael Clarke made 34 as the Australians were bowled out in 46.4 overs.
Veteran fast bowler Brett Lee made Pakistan battle as he claimed four wickets but Asad Shafiq continued his promising start to his international career with 46 and 20-year-old Umar Akmal was unbeaten at the end on 44.
With Pakistan teetering a little on 142-6, Razzaq weighed in with 20 off 24 balls to guide his team home with nine overs to spare.
South Africa secured a fifth win in six outings by ending Bangladesh's hopes of progressing with a one-sided victory in Dhaka.
Jacques Kallis (69), Faf du Plessis (52) and opener Hashim Amla (51) all made half-centuries as the Proteas compiled a daunting 284-8, with captain Graeme Smith contributing 45 to a first-wicket stand of 97.
Bangladesh then collapsed to 78 all out, mirroring the earlier capitulation against the West Indies which yielded 20 fewer runs.
Left-arm fast bowler Lonwabo Tsotsobe claimed three early wickets, and spin bowler Robin Peterson continued the steady flow of departing batsmen with impressive figures of 4-12 from his seven overs.