It's been four years since wildcard Kim Clijsters won the U.S. Open. In that time her world changed. Fresh-faced and fit, the wife and mother has intertwined happy-go-lucky with her unbending work ethic to strike a harmonious and effective chord. So far.

Serena Williams stands like barbed-wire barricade between her and a berth in the final, and everyone is watching.

Today two other U.S. Open champions—and mothers—contemplated Clijsters run and wondered if they coulda, woulda, shoulda.

Six-time U.S. Open champ Chris Evert, who was in a midtown studio today on a satellite TV tour to promote Hood Simply Smart milk: "I really admire Kim Clijsters. In my era Evonne Goolagong had two children and she was playing. And Margaret Court had children. I don't know if I could ever be a mother and try to separate the tennis from going home and trying to fulfill their needs. I had to be singleminded. I had to be able to do one thing, so I admire that Kim can do both—and she looks fit and better than ever."

Goolagong achieved her final major victory, the 1980 Wimbledon Ladies' Championship, as a mother. At that time it had been 66 years since a mother had lifted the Venus Rosewater Dish.

Five-time U.S. Open champ Stefanie Graf, who rallied with kids today in Grand Central Terminal in a Longines-sponsored event, has brought her children to Arthur Ashe Stadium as spectators. Assessing her own suspected abilities to manage mother and competitor duties, Graf was resolute: "I personally wouldn't have, but I certainly have a lot of respect for who can and watching Kim, and seeing her enjoyment of doing it. Taking that time off probably rejuvenated her, but it can't be an easy thing with a young toddler so I admire that she's capable of balancing that."

Clijsters, like most players, travels with an entourage. Hers includes husband, baby and nanny. Roger Federer is another with his wife and twin girls along for the ride. Angela Buxton, a member of the U.S. Open Final 8 Club who reached No. 5 in the world in 1956, recalls the early days, before players had entourages of any kind.

"When I was playing there was no money in the game," said Buxton, from her midtown suite, in town for the U.S. Open fortnight. "There was nothing at all like bringing wives and husbands along. Most people couldn't afford that, you know. If you were a woman player, by the time you had a wedding ring on your finger it was time to hang up your racquets—that was the end of that."

Margaret Smith Court, as Evert said, was the first, in Buxton's memory, to bring home on the road. "She started to bring her husband and baby along—and he seemed to be hanging on to the baby. We all thought how very nice that was. It didn't seem to interfere with because she still did quite a lot of winning after that."

Court's fifth U.S. Open title came one year after the birth of her first child. If the rain holds off tomorrow and Clijsters staves off Serena, she'll have a chance at a second U.S. Open singles title.

Wistful is how Buxton sounds when contemplating such a chance. "I had one baby after another baby very quickly. There was only 17 months between them," she said, " I was thinking of coming back. I did have a nanny, but I never got the chance. So I can understand the feeling.

"I take my hat off to Kim Clijsters," Buxton declares. "She is superb! She must have done a lot of training to get back so quickly. It is like she hasn't been away. One looks and thinks, Wasn't it last week she got to the finals here and won this? But it's four years ago, 2005."

This story was adapted for an article that ran in today's San Francisco Chronicle.