Serena Williams is considering playing one more tournament in her comeback from injury before the US Open starts on August 28.
Sidelined for six months this season because of a chronic knee problem, Williams could compete at next week's Rogers Cup in Montreal or the New Haven, Connecticut event that follows.
"It's real, real tempting," the former world number one told reporters after reaching the Los Angeles Open semi-finals with a 6-7, 6-1, 6-4 win over fellow American Meghann Shaughnessy on Friday.
"But I'm taking it one match at a time."
Williams has slipped to 110th in the world rankings because of her inactivity this year and would need to return to the top 32 to be seeded at the US Open.
Should she win this week's final at the Home Depot Center, she would be on the brink of the top 50, a further enticement to fit in one more tournament before the year's final grand slam.
Williams, who lost to Russian Vera Zvonareva in the semi-finals of last month's Cincinnati Open, her first event since the Australian Open in January, then played down her plans.
"I can't dwell on that, if I win here and if I win there," she said. "That's crazy."
The greatest encouragement for the 24-year-old on her comeback trail has been her improving fitness.
She has to overcome a strong challenge by Shaughnessy before winning their quarter-final, having rallied from a set down to beat Slovakian Daniela Hantuchova in the previous round.
"I'm most proud about the fact that I'm not tired after a long match," twice champion Williams said after an encounter that lasted just over two-and-a-half hours in sapping heat.
"Usually after a long match, I get sore. But I don't feel that way at all. I felt I could have stayed out there a couple of hours longer.
"My body isn't sore and my muscles are fine. I'm really relaxed out there and it's just fun to be able to play different players and to compete hard."
By reaching the last four in Los Angeles, Williams should improve to around 75th in next week's world rankings.
"I have new goals now," she said. "I'm reaching for the top 50. Maybe I'll get there. I think I'm definitely worthy."
A twice US Open champion, Williams claimed her first grand slam crown in New York in 1999.