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Williams could meet younger sister Serena in the final
Venus Williams stepped up her Wimbledon preparations by beating Andrea Petkovic 7-5 5-7 6-3 in the first round of the Aegon International at Eastbourne.
The five-time Wimbledon champion has slipped to number 32 in the world after a run of injuries but looked in strong form to move past eighth seed Petkovic.
Williams, 31 this week, grew in stature as the match wore on but did hit three double faults on her way to victory.
She will now face either Ana Ivanovic or Julia Goerges in the second round.
Petkovic was Venus's opponent when she retired with a hip injury from January's Australian Open and showed her class by winning a close second set.
Venus excited to be back at Eastbourne
Venus said: "It was definitely an adventure.
"I was falling down every other point, coming back from such a long layoff, competing against someone who's been playing so well in the last 12 months.
"I was extremely excited to come back with the win. More than anything I was just really extremely excited to have the opportunity to play another match."
Australia was the American's last tournament appearance and the winner of seven Grand Slam singles titles will now be eyeing a final against
Serena takes on Bulgaria's Tsvetana Pironkova in the first round and has not played a competitive match since regaining the Wimbledon crown a year ago to secure a 13th Grand Slam singles title.
The world number 25 cut her foot on glass in a restaurant when celebrating her Wimbledon 2010 triumph, then in February underwent emergency surgery for a blood clot on her lung.
Third seed Victoria Azarenka from Belarus made easy progress as she beat Peng Shuai 6-4 7-6 (7-2) while number five seed Petra Kvitova struggled on her way to victory over Anastasija Sevastova.
Kvitova dropped the first set before coming through 5-7 6-1 6-3.
British number three
went out to Croatia's Mirjana Lucic in the final qualifying round.
The 27-year-old Londoner, ranked 110, overcame world number 78 Sorana Cirstea 6-3 6-3 on Centre Court in the second qualifying round but found Lucic a step too far.
Lucic won 7-5 6-1 to book her place in the main draw.
came through a battle in the final round of men's qualifying as he defeated Russia's Denis Matsukevich 6-1 2-6 7-6 (7-4).
was no match for Bulgarian Grigor Dimitrov and went down 2-6 7-6 (7-5) 6-4 while
lost 6-3 6-4 to Radek Stepanek.
- fresh from his run to the semi-finals of Queen's - was unfortunate to lose his doubles match alongside
The duo lost out to Marcelo Melo and Bruno Soares from Brazil in a champions tie break as they went down 6-7 (8-6) 6-4 10-6