Complete the following sentence: Petkovic's final match of 2012 was on 29 December in the
2013 Hopman Cup against Ashleigh Barty. She won the first set 6<unk>4 but appeared to be suffering from a knee injury late on in the set. She won the first set 6<unk>4 but appeared to be suffering from a knee injury late on in the set. ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️