Melbourne - Venus Williams insisted she was not at the Australian Open to make up the numbers on Saturday after making the last 16 at Melbourne Park, saying she aimed to win every tournament she entered.
The 34-year-old American, who claimed the last of her seven majors at Wimbledon in 2008 and has not reached the second week of a Grand Slam since 2011, said her vast experience should not be underestimated.
"I've won big. It's not like I haven't done it before," she said after a gritty 4-6, 7-6 (7/3), 6-1 win over Camila Giorgi of Italy.
"For me, I like to win titles, whether it's a smaller event or a big event. That's what I play for.
"So, yes, great, it's great to be in the second week. But is the fourth round my goal when I come to these tournaments? No."
The win takes the 18th seeded American's record for 2015 to 8-0, including winning the Auckland Classic lead-up event.
Williams said she was overjoyed to advance so far at a major again after a long battle with the energy-sapping Sjogren's Syndrome, which was diagnosed in 2011, and a string of injuries.
"That feels fantastic, especially when you have things happen in your life which are out of your control. I don't want to leave it at that, I'll try to keep going," she said, clearly enjoying the moment in front of an appreciative crowd.
The American, whose ranking will rise to 12th after the tournament and could climb higher, said it had been a long road back.
"Yeah, definitely years go by fast," she said. "It's been a lot of work and a lot of learning and a lot of perseverance. It will continue to be that for me. Just have to come to terms with it."
Williams will meet sixth seed Agnieszka Radwanska of Poland in the fourth round, a player who has won their last two encounters.
"Well this little cat has a few tricks left," she said.
She looked down and out with Giorgi serving for the match at 5-4 but broke back to love to stay alive.
Williams went ahead 6-5 and had two set points with Giorgi serving but fired both chances into the net as the Italian hung on to force a tie-break.
Despite a hiccup when she double faulted at 2-2, Williams won the tie-break 7-3 to take the match to a third set with momentum on her side.
She went up a break and Giorgi immediately broke back, but it was the last resistance from the Italian as Williams cruised through the third set, raising both hands to the wildly cheering crowd after sealing the win.