The 19-year-old Swiss, who secured her return to the world number one spot by reaching the final of the $535,000 Hamburg Cup, said she would stay in professional tennis only as long as she was at the top of her game.
``I couldn't see myself playing until I'm 30, not right now,'' said Hingis who has played competitively since she was four.
``The older I get, I see it gets harder and harder,'' she said. ``Results like Steffi or other top players got over the years -- I have great respect for that.''
Hingis starts her 137th week at number one on Monday when she replaces Lindsay Davenport. At the height of her career Graf notched up 186 consecutive weeks at the head of the rankings and holds the all-time record of 377 weeks in the top spot.
Although it was nice to oust Davenport, Hingis said her main aim was to be in pole position at the end of the year, as she was both last year and in 1997.
Winning tournaments therefore had to be the priority. ``If you play well and get the results, ranking comes automatically,'' she said.
TOUGH AT THE TOP
Hingis said she felt the demands on young players had become greater, and said her fitness and ability to give 100 percent would be the key factor in any decision on her playing future.
``But maybe I'll change my opinion in a few more years,'' she added, pointing to Graf's ability to stay at the top until she retired last year.
``Everyone's saying they will stop at 24 or 25, but players like Steffi for example still go on. When you can still hold up top players, why should you stop?''
Hingis said she was already finding it important to pace herself and marvelled at players who competed for five or six weeks at a time without taking a break.
She said her main aim was to retain the form needed to fight off challenges for the number one spot from Davenport and Venus Williams, who came back from a 5-1/2 month injury lay-off this week.
``My own playing style has brought me pretty far,'' she said. ``You don't always need a model.''