Australia beat West Germany 2-1 Saturday to advance to the final of the inaugural Hopman Cup international team tennis tournament. Led by Pat Cash, Australia earned a berth in the finals Sunday against Czechoslovakia, which beat Sweden on Friday.

Cash, coming off a four-month layoff due to injury, secured the victory by downing Patrick Kuhnen in the final singles match, 6-3, 7-6 (11-9).Steffi Graf gave West Germany a 1-0 lead by beating an out-of-form Hana Mandlikova 6-0, 6-1. But Cash and Mandlikova rallied to beat Graf and Kuhnen 6-4, 6-2 in the mixed doubles.

Nationally . . .