Flavia Pennetta beats Sloane Stephens to make Indian Wells semifinals

Flavia Pennetta came through in windy conditions at Indian Wells. (Stephen Dunn/Getty Images)

INDIAN WELLS, Calif. -- Sloane Stephens' career-best run at the BNP Paribas Open ended with a 6-4, 5-7, 6-4 loss to No. 21 Flavia Pennetta in a wind-swept quarterfinal on Thursday.

The topsy-turvy match won't be remembered for high-quality tennis. Stephens, the first American woman to make quarterfinals since 2008, couldn't overcome her own patchy play or the swirling wind that derailed the final set. Pennetta, who became the first Italian woman to make the semifinals here, described the final set of tennis "a disaster."

"We didn't have a lot of fun today," Pennetta said. "I think it was not nice tennis on court. We didn't play our best tennis."

Pennetta served for the match at 5-4 in the second set, but she played an error-strewn game to give Stephens the break.That was the first of six consecutive games won for Stephens, who rallied to win the second set and open a 3-0 lead in the third. Pennetta, however, was able to come back by playing some safe, smart tennis in difficult conditions to reach her first semifinal of the season.

"I didn't accept [the wind] for I think seven, eight minutes, and I went 3‑love down [in the third set] in nine minutes," Pennetta said. "And then I started to come back, to play every point, and it was not easy also for her to play. She was in the same situation as me, no feeling at all. I mean, it was impossible today."

Being unable to close out the match was a tough ending to a strong tournament for Stephens, who played some of her best tennis of the season.

"I played some really good matches, and it's unfortunate that it just got really windy and it was up and down like that," she said. "She was playing really well in the first two sets either way. She deserved to win today, and it's kind of like that sometimes."

Stephens will head to next week's Sony Open with confidence knowing the work she's put in recently with new coach Paul Annacone is paying off. She still is trying to make her first WTA final (let alone win one), and her play at Indian Wells was clearly a step in the right direction of earning better results outside of the Grand Slam tournaments.

"I feel a lot better about myself on court, so I think that's a good thing," she said. "It takes time and I'm in no rush. People are like, 'When are you going to win a tournament? When are you going to do this?' I'm like, 'Whatever, doesn't matter.'"

Pennetta will play top seed Li Na in Friday night's semifinal, which will feature two 32-year-olds separated by one day (the Italian is older). Li had her own troubles in Thursday's first quarterfinal, defeating Dominika Cibulkova 6-3, 4-6, 6-3 in an Australian Open final rematch that featured a combined 112 unforced errors. Li blamed a loss of focus early in the second set for a dip in form that let Cibulkova back into the match. She was so out of it she thought it was a full changeover after the first game of the set.

"After that game I was feeling like my mind was somewhere else, and I think I drop the level [of play] so fast," Li said.

Li dominated Pennetta 6-2, 6-2 in the Australian Open quarterfinals. Asked what what troubles her about Li's game, Pennetta smiled and said, "Everything. No, she plays more or less like me, but she's more powerful than me. I have to be real aggressive, but it's not going to be easy. She's so good. She's played unbelievable this year. In Australia ... I didn't have any chance at all. I hope tomorrow to have a little bit of a chance."

In the other semifinal, Simona Halep will try to celebrate her top-five debut with a win over Agnieszka Radwanska. The third-ranked Radwanska leads the head-to-head 3-2 but lost to Halep 7-5, 6-2 at the Qatar Open last month. Radwanska led 5-2 in the first set before Halep stormed back to win seven straight games and roll to victory. Radwanska said she didn't feel she played poorly and that Halep was just too solid to break down. That's a tremendous compliment to the Romanian, who is two matches away from the biggest title of her career.

"I started the match with one tactic, but it wasn't too good," Halep said this week, recalling that comeback win. "I wanted to hit every ball, and she likes this game. Then I said, I have to change something. I was opening the court more and [creating] good angles. I started to finish the point very quickly, because if you stay more in the rallies with Radwanska, it's not easy. You have to run a lot. She's very smart player, and I wanted to play the same, like smart, smart aggressive."