Venus Williams hit out at having to answer "crazy questions" about her future in the game after suffering her worst Wimbledon defeat in 15 years.
The 32-year-old five-times champion refuses to be hounded into retirement and said just being back playing after recovering from Sjogren's Syndrome - an energy-sapping disease which causes joint pain and fatigue - was a "big victory".
"There's no way I'm just going to sit down and give up just because I have a hard time the first five or six freakin' tournaments back," Williams said after her 6-1 6-3 first-round loss to world No.79 Elena Vesnina on Monday.
"That's just not me. I feel like I am a great player - I am a great player.
"Unfortunately, I had a deal with circumstances that people don't normally have to deal with in this sport.
"But I can't be discouraged by that, so I'm up for challenges. I have great tennis in me. I just need the opportunity."
Williams' defeat was her first opening-round loss at the All England Club since making her debut in 1997 and the former world No.1 also crashed out in the second round at the French Open last month.
But the seven-times major champion has posted victories over top-five stars Petra Kvitova and Samantha Stosur this year and took offence when asked about her current struggles to win matches.
"Am I struggling? Am I? I don't know. Tell me what the struggle is," Williams snapped during her post-match media conference.
"I've been through a lot for years without knowing what I was going through.
"It's all a culmination at the end of the day. I just try to stay positive and focused on the tennis, not let anything get to me, like, you know, crazy questions.
"I'm tough. Let me tell you, tough as nails."
Williams has slipped to world No.58 after her six months fighting serious illness but said her priority now was being ready for next month's "Wimbledon" Olympics.
Already a triple gold medallist, Williams also vowed to return to the All England Club for a 17th consecutive Wimbledon campaign in 2013.
Her loss to Vesnina was just her fourth defeat at the first-round stage in 56 grand slams.
Williams said she'd continue to draw inspiration from younger sister Serena as she tries to claw her way back up the rankings.
"She's fought back near-death experiences - several," Williams said.
"I'm very motivated by her and nothing getting her down and everything that she's been through that no one even knows about. That's definitely inspirational, that in itself.
"There's been a lot of people in this world that fought back from the brink.
"I don't have time to feel sorry for myself because of everything that's going on. I have to be positive.
"I love this sport. I feel like I can play well and I'm not going to give up on that.
"I don't have time to be negative."
While Williams is gone, the rest of the women's big names are up and away with world No.1 Maria Sharapova leading a raft of seeds through to the second round.
Sharapova swept past Australian Anastasia Rodionova 6-2 6-3 in her first match since completing her career grand slam at the French Open.
Polish third seed Agnieszka Radwanska, Australian fifth seed Samantha Stosur, China's 11th seed Li Na and former world No.1 Kim Clijsters - in her Wimbledon swan song - also safely advanced to second-round matches on Wednesday.