US Open 2015: Serena Williams aims to equal Steffi Graf's record

Serena Williams holds all four Grand Slam titles

As Serena Williams chases history at the US Open, her coach Patrick Mouratoglou says he is "completely convinced" she is going to beat Steffi Graf's record tally of Grand Slam titles.

Williams will become the first player to complete the calendar Grand Slam since Graf in 1988 if she wins in New York, and will also draw level with the German's Open era record of 22 major titles.

"I'm completely convinced she is going to beat the record of Steffi, and maybe even the other one [Margaret Court's all-time record of 24 Grand Slams]," Mouratoglou told BBC Sport.

Serena Williams is looking to win her seventh US Open and complete a Grand Slam of major titles in 2015

"It's just a question of time, and for me this is the really big deal.

"We spoke several times about making history and finding a way to be the greatest of all time and I think there is nothing more motivating than that."

The US Open starts on Monday and the American's match against Russia's world number 86 Vitalia Diatchenko opens the first night session at 00:00 BST.

'Her father built her mentally'

Williams has won eight of the 13 Grand Slam titles on offer since starting work with Mouratoglou in the run-up to Wimbledon 2012.

The Frenchman's focus on her place in history has been an important motivational tool in that time, and one month before her 34th birthday, there has been no talk of retirement.

Williams says the pressure she encountered at Wimbledon - where she won the title to hold all four Grand Slams simultaneously - was perfect preparation for her attempt to win all four in the same year for the first time in her career.

Mental strength, though, is a Williams family trait - as Mouratoglou knows well.

"He [her father Richard] totally built her. He built her mentally. It was one of his main goals to build two human beings with an incredible confidence and he succeeded in that.

"Even 5-0 and match points down in the third, she would still think she could make it - and she's right, she can."

'I'm obviously going to be here next year'

Williams underlined that point perfectly at the French Open, where she found herself in several precarious positions and had to win a deciding set in five of her seven matches.

She was unwell in Paris, and was sick during January's Australian Open final against Maria Sharapova.

"Even sick, she remains the best," seven-time Grand Slam champion Justine Henin told the BBC at Roland Garros, and now Williams has the chance to prove beyond doubt that she is the best of all time.

Williams won the French Open in June (left) following her success in the Australian Open at the start of the year

"If things don't work out this year, I'm obviously going to be here next year and have another chance," the world number one said in her pre-tournament media conference.

"I never really thought I would be in this position where I would even be talking about passing Steffi Graf, or even mentioning Margaret Court.

"I just grew up trying to be the best that I could."

The locker room view

Maria Sharapova, world number three: "It's just a huge bonus for her to be in this position this way. Being back here where she has made so many great memories will make it a great story."

Simona Halep, world number two: "If I'm not in the final, then I want her to win. If I'm in the final with her, then I want to win."

Caroline Wozniacki, 2014 runner-up: "What she's about to do and what she's done is amazing. I'm in the other half of the draw. Hopefully we can do a re-run of [the final] last year."

Heather Watson, two points from defeating Williams at Wimbledon: "It would be amazing for her, and it's looking very likely."

Novak Djokovic, nine-time Grand Slam champion: "I am sending her good vibes. I know how tough it is."

Roger Federer, 17-time Grand Slam champion: "You don't get this opportunity many times in your career or in tennis, for that matter."