No.7 seed Danielle Collins kept her hopes for a title on home soil alive, as she upset No.2 seed Elena Rybakina of Kazakhstan, 7-6(5), 7-6(4) to reach the semifinals of the Mubadala Silicon Valley Classic.

"It was weird, even though I won both sets, I felt like I was always playing from behind," Collins said to the media, after the victory. "To win a match where you always feel like you’re playing from behind, it’s very rewarding, but during the process, it can be a little nerve-wracking. I was happy that I kept my composure for the most part, and pulled out the win."

In the first meeting between the pair, World No.36 Collins scored her third Top 20 victory of the season after just under two hours, improving her winning streak to eight straight matches.

The American is coming off a maiden WTA singles title at her most recent event, on the clay courts of Palermo. The victory over World No.20 Rybakina, a semifinalist at the Tokyo Olympic Games, is Collins's best victory by ranking during her recent undefeated run.

To get this win over Rybakina, Collins had to fight through two challenging tiebreak sets, which included saving a pair of set points in the opening frame. But Collins was sturdy in moments of adversity like those, and she saved six of the seven break points she faced in the tilt overall.

In fact, the only time Collins faltered while facing break point was in the very first game of the match. Collins double faulted in that game to give Rybakina the chance, which the Kazakh converted with a winning forehand.

Collins, though, demonstrated her mettle by saving two set points at 5-3, then broke Rybakina when the No.2 seed served for the set, leveling the opener at 5-5. A tiebreak ensued, where Collins took immediate control, leaping ahead 4-0 before holding on for the one-set lead.

There were no breaks of serve in the second set -- Rybakina never even faced a break point -- as the combatants inexorably moved to another tiebreak. Once again, Collins hit the changeover with the lead, ahead 4-2, and the American used two outstanding serves to clinch the final two points of the upset.

In the semifinals, Collins will face resurgent qualifier Ana Konjuh of Croatia, who overcame Zhang Shuai of China, 3-6, 6-2, 6-0 in an earlier quarterfinal on Stadium Court.

Konjuh had defeated Zhang in their two previous meetings -- in their most recent clash in 2017, she dropped just a single game. Despite the long gap between that encounter and this one, the result was the same in the end, as Konjuh collected a comeback win after an hour and 39 minutes of play.

"I came here not really expecting this," Konjuh told the press, after her win. "Like, if I go through qualifying, into the main draw, it would be nice, just to be at high-level tournaments again. So this was kind of unexpected, but I’m not complaining at all!"

Former Top 20 player Konjuh began the year ranked World No.538, having missed much of the 2020 season due to elbow injury woes. But the Croat has quickly stormed back up the rankings in 2021, currently sitting at World No.116 and edging closer to a return to the Top 100.

Konjuh improves to 3-0 vs. Zhang with San Jose QF win: Highlights

2021 San Jose

After a trip to the Belgrade final earlier this season, Konjuh finds herself in her second semifinal of the year, following two wins in qualifying and three main-draw victories this week. Konjuh has surpassed her previous best result at this event, a quarterfinal showing in 2017.

Hard-hitting Konjuh was undone by 17 unforced errors in the first set as World No.51 Zhang charged to the one-set lead. But Konjuh tightened up her game in the second set, with nine winners to just three unforced errors during that timeframe as she tied up the match.

Former Top 25 player Zhang held a break point in the opening game of the final set, but Konjuh blasted her way out of that jam before powering her way through the decider. All told, Konjuh won the last ten games of the match to sweep into the semifinals.

"A key was, I think, keeping my serve, just being focused, and making her play one more ball each point," Konjuh said. "I won a lot of those key points, so I was really happy in the end."