Serena Williams’ comeback ran out of steam at Eastbourne on Wednesday as she lost 3-6, 7-6 (5), 7-5 to top-seeded Vera Zvonareva in the second round.

Zvonareva came through a tense tussle in 3 hours, 12 minutes for only her second win in eight matches against the 13-time Grand Slam champion.

“I know I can do better,” Williams said. “I can improve and I’m so close to being there, it’s good.”

The No. 3-ranked Russian gained a measure of revenge for her 6-3, 6-2 loss in last year’s Wimbledon final that turned out to be Williams’ last match for almost a year as she recovered from a cut on her foot which led to blood clots on her lungs.

Williams drew on her trademark fighting spirit in the deciding set as she came back from 5-2 down to make it 5-5, saving three match points at 5-4. But Zvonareva immediately broke again and a tiring Williams couldn’t muster another fightback.

On the day she was awarded a Wimbledon seeding of seventh, 19 places above her world ranking, Williams was beaten on grass for the first time since she lost the 2008 final at the All England Club to her sister Venus.

However, the four-time Wimbledon winner said she was happy with her preparations for the defense of her title—and even happier that the foot injury was no longer troubling her.

“It was a good two matches for me,” Serena said. “I couldn’t be happier with the amount of tennis I played so it’s good, just keep going.

“I haven’t played in almost a year so I’m a little sore. But it’s good that I’m sore now because hopefully next week I won’t be as sore. (The foot) is holding up really well and I’m just really excited about that.”

Returning from her own injury layoff, Venus Williams had earlier reached the quarterfinals with a convincing 6-3, 6-2 win over Ana Ivanovic, and her younger sister looked set to join her in the last eight when she served for the match at 5-4 in the second set.

But when facing a break point, Serena double-faulted and Zvonareva suddenly rediscovered her confidence. Leading 6-5 in the tiebreaker, the Russian drove a forehand into the corner, with Serena on her backside after slipping on the baseline.

Trailing 5-4 in the decider, Serena hopped on one foot and looked surprised and relieved as a bold backhand winner looped onto the line to save a second match point. She went on to break back with another brutal backhand winner.

But Serena was broken in the next game and Zvonareva wouldn’t be denied again. She moved into a 40-0 lead and then powered a forehand winner onto the baseline to claim victory on her fourth match point.

“It’s never easy against Serena,” Zvonareva said. “She’s a great fighter and she came up with some great shots at the very important moments. I kept fighting and I’m really happy I won it.”

Venus, playing her second match following a five-month layoff, will face Daniela Hantuchova in the quarterfinals after easing past Ivanovic. The five-time Wimbledon champion didn’t face a single break point in the first set while breaking Ivanovic twice.

Ivanovic had her only break point at 1-0 in the second set but Venus sent down a 196 kph (122 mph) first serve to save it before breaking twice more and improving her record against Ivanovic to 7-1.

“Right now I feel that I’m playing very tough and I’m playing well on the big points,” Venus said. “These matches have been huge and crucial for me to just get back in the swing of things.