Agnieszka Radwanska has insisted that an ageing Venus Williams will still present a "great challenge" in the fourth round of the Australian Open.
The 34-year-old American won the last of her eight Grand Slams in 2008, but world number six Radwanska is adamant that she continues to be a dangerous opponent.
"I think playing her is always great challenge," she told reporters. "I think she is still playing great tennis even she's a bit older. She's still really fit and playing a high level.
"I think it's going to be another good match."
Williams currently edges the head-to-head record between the pair, winning five of their nine matches.