Serena Williams does not feel 'any pressure or stress' ahead of Wimbledon

The 34-year-old American sealed a self-described 'Serena Slam' last year with her victory over Garbine Muguruza in the All England Club final.

It followed her 2014 US Open win and triumphs at the Australian Open and French Open early in 2015, making Williams champion of all four majors at the same time, for the second time in her career.

However, hopes of a calendar Grand Slam of all four majors in the same year were left in tatters by a startling US Open semi-final loss to Italian Roberta Vinci, while defeats by Angelique Kerber in January's Australian Open final and Muguruza in this month's French Open title match have left questions being asked of Williams.

Steffi Graf's Open era record of 22 majors is the next landmark for the American, but talk about records does not stimulate Williams and she gave clipped responses to much of the questioning she faced two days out from her opening match against 27-year-old Swiss qualifier Amra Sadikovic.

"This year I don't feel as much tension as I usually do," Williams said. “Well, there's some years I haven't felt any tension either. I'm feeling pretty good. I don't feel any pressure or stress.

"I think it's important to learn from every loss that you have. Throughout my whole career I have been able to learn a lot, to come back a much better player.

"I'm definitely ready to start playing at this point. I'm kind of over-practising every day for two hours, then going to the gym for some time."

She remains the women's world number one and the player to beat, in what otherwise looks a wide open field.

Muguruza has experienced mixed fortunes since surprising many with her run to the final on grass - a surface she once loathed - last year. The French Open title, and the way she saw off Williams in straight sets to earn that maiden grand slam, means she may be a serious contender.

But all eyes will be on Williams, and when it comes to match time that is how she likes it. The stadium court is her playground, and she is relishing her return there.

"It's just that one time a year you get to play on this amazing, beautiful surface - it feels really good," Williams said.

But the defending champion would not be drawn on discussing the fate of the 2004 Wimbledon champion Maria Sharapova, who is challenging a two-year ban for a doping offence.

"I've commented a lot on that in the past," Williams said, dismissing the enquiry.

Williams did, however, admit that she was worried about the Zika virus and its impact on the Olympics, even though she has no plans to skip the Rio Games: "There's really been a lot of instructions. I'm concerned, obviously, but I'm also very prepared."

Williams arrived in London on Monday and has been involved in a host of corporate events alongside her practice, such is the life of the modern superstar sportswoman.

From belting out Irene Cara's What A Feeling at an airline-sponsored karaoke event, to promoting her own new signature clothing line, holding a Facebook Q&A and attending the Women's Tennis Association's pre-Wimbledon party, Williams has been busy during her week in the English capital.

Now she means business with racket in hand, and she has the fond memories of her six Wimbledon titles and two 'Serena Slams' to fuel the drive for success.

“It was a great accomplishment to win four grand slams in a row twice in my career,” she said. “It's pretty cool. It's really awesome."

Few would be against another cool and awesome fortnight ahead for the record-breaking American.