London - Wimbledon champion Serena Williams has revealed a pep talk from her sister Venus is the driving force behind her bid to win the title for a sixth time.
For the first time since making her Wimbledon debut in 1998, Serena has travelled to the All England Club without Venus, who was forced to withdraw from the tournament due to a back injury.
Venus's absence is a blow to Serena's morale given the world number one's close relationship with her older sister.
They share a Florida home and always lived in the same rented accommodation near Wimbledon during the grass-court Grand Slam.
But Venus ensured Serena made the journey to south-west London in business-like fashion after urging the 31-year-old American to win a sixth title.
That would surpass Venus's haul of five Wimbledon crowns and give Serena her 17th Grand Slam success.
"For me there is no family competition, but this is the first year I've played Wimbledon and Venus hasn't been here," Serena said on Sunday.
"I feel so lonely. I feel like something is missing.
"It's incredibly disappointing. We always used to stay together and I'm still staying in the small room because she always had the bigger room.
"I feel every time I walk into the home I'm a little sad. I look in her room and she always had music in the morning. We kind of always danced in the morning.
"She's definitely really missed. And we're defending champions in doubles, so, yeah, I'm really bummed out about it.
"But before I left, she said; 'Snap out of it. It's time for you to pass me'. So that was really encouraging. Hopefully I'll be able to do it."
Serena opens her title defence against Luxembourg's Mandy Minella on Tuesday and the world number 92 is unlikely to pose any kind of threat given the American's astonishing record over the last 12 months.
Since an embarrassing first round loss against Virginie Razzano at last year's French Open, Williams has simply been unstoppable, winning 74 of her 77 matches and collecting the Wimbledon, US Open, French Open and Olympic titles in the process.
Much of the credit goes to Frenchman Patrick Mouratoglou, who has managed to coax a more focused approach to the sport since becoming Serena's coach last year, while also becoming romantically involved with the American.
"Patrick, he means a lot to me," Serena said. "I was just talking to him randomly a couple days ago, and I said; 'Wow, in a year we've won three Grand Slams, two gold medals, a Championships. And he said; 'You've won 74-3'. That's pretty good'. But I said; 'No, it could be better'.
"I appreciate that we can definitely continue to motivate each other.
"I would say that I am definitely an intense person. But I think the intensity is now all towards the game, like all towards when I play, all towards hitting the ball.
"So I think I take more pride into every stroke, into every tournament that I play, into every match that I play, and I think that's one big change that has happened in my career."
Given Serena's dominant record against her main rivals Maria Sharapova and Victoria Azarenka, few would bet against Williams lifting the Venus Rosewater Dish for the fourth time in five years.
But Williams struck a cautious note, insisting she would rather not have the extra pressure of being favourite.
"Last year I had no pressure because I lost fairly early the year before so no one put me as the top to win," she said.
"When I'm going into a tournament and I'm not the favourite, it always feels good.
"This year, it's definitely a little more pressure being the favourite. But as Billie Jean King said; 'Pressure's a privilege' and I take it as a privilege."