Editor's note: Steffi Graf has remained relatively low key during Serena Williams' quest for history, a decision the 1988 season Slam winner made in an effort to not take away any of the spotlight from Williams. But ESPN tennis analyst Darren Cahill recently had an opportunity to sit down with Graf and discuss what Williams must be feeling -- among other topics.
1. What will be going through your mind as Serena tries to match your total of 22 career major championships?
This is a special time for any fan of tennis, any fan of sport in general. Everyone should cherish the chance to watch an amazing player achieve such an incredible milestone. Personally, it's refreshed my love of tennis, and it's deepened my gratitude to the sport for all that it's given me, my family, my foundation and all the time I get to spend with both.
2. What do you think will happen to the women's game -- in terms of popularity and competitiveness -- when Serena retires?
There's no question that Serena retiring will be a sad day. However, she is leaving the game so much better off than it was, so that's reason to celebrate. And there is always the hope, if history is any indicator, that she will have a worthy successor.
3. How would you describe Serena's legacy?
Serena's legacy has yet to be fully written. But I would describe it, to this point, as remarkable. With her athleticism, her power, her serve, she's already changed the game. And she's not done.
4. How was the pressure to complete a calendar Slam different from the pressure to win an individual tournament?
The more you care, the more pressure you feel. The difficulty in my career was how much I cared, always. The pressure you put on yourself as a player, I believe, is the greatest pressure of all. And I felt that weight so keenly every time I stepped onto the court, no matter the occasion.
5. You won your Grand Slam near the start of your career, while Serena is obviously toward the end of hers. How might age affect her pursuit?
It's hard at any age. When you're young there's the luxury of thinking you will have other opportunities, which relieves some of the pressure -- but you also lack the experience. When you're older you have the experience, but you're also so much more aware of time passing, which increases the pressure.
6. What memories and feelings stand out most from winning the Grand Slam in 1988?
The moment of sheer joy and incredible relief in realizing I did it.
7. What were the biggest obstacles for you physically and mentally to winning all four majors in 1988?
I couldn't envision it. I couldn't conceive it. Being only 18 years old, having won only one major going into 1988, one of the greatest challenges was simply believing in myself and having confidence that I could accomplish such a thing. Not to mention the difficulty of staying healthy and focused throughout the whole year.
8. What are your thoughts on the pressure Serena faces at the US Open?
The pressure of winning a calendar slam grows as you get closer and closer to the finish line. It will build with each win. But I believe she will do great. Serena has shown her whole career that she knows how to handle pressure incredibly well.
9. When Serena decides to stop playing, how many majors do you think she'll have won, and what will be her place in the history of the game?
That will be up to Serena. It's all in her hands. If she stays healthy and committed there's no doubt that she will continue to break records.
10. What are your expectations of Serena in the 2015 US Open?
I expect her to give it all she has, with no regrets.