CHARLESTON, S.C. -- Serena Williams had completed a dazzling display of tennis to dominate her opponent and advance to her fourth finals of the year at the Family Circle Cup on Saturday.

Her excitement, though, was over the weeklong play of sister Venus despite big sister's inability to slow down Serena.

"She's had a great week," Serena said

So has Serena, who won her 14th straight match here with a 6-1, 6-2 victory over Venus Williams - the most one-sided result in the sisters' long, intense rivalry.

Serena got started early with her powerhouse serves and rarely let Venus gain any ground.

Still, Serena understands better than almost anyone what her older sister has gone through in recent years due to injury and illness.

"I think (the week) is positive looking for her and she can see the next, her next tournament be really more positive," Serena said.

Serena Williams goes for her second straight tournament title and third here overall Sunday when she'll take on Jelena Jankovic, a three-set winner over Stefanie Voegele.

It was the first time since 2009 the Williams sisters were playing each other in a tournament and the excitement was felt throughout the Family Circle Tennis Center. A crowd of 9,538 filled Billie Jean King Court, a single-session record since the tournament moved from Hilton Head to Charleston in 2001.

Serena has won five straight in their series and leads 14-10 since they first faced each other at the Australian Open in 1998. Back then, Venus was the more polished player and began a run of five victories over Serena the first six times they played.

Things turned in 2002 with Serena's 6-2, 6-2 win in Miami, the previous biggest sibling margin before this one.

Since, Serena holds a 13-5 mark and has played some of her best tennis the past year.

Since capturing this title in April 2012, Serena has won Wimbledon, Olympic gold, the U.S. Open and reclaimed the world's No. 1 ranking.

"Obviously, Serena is playing extremely well," Venus says, "and it's great to see her at No. 1 and just fulfilling every dream."

Venus Williams' career hasn't gone as well. The 32-year-old seven-time major champion was diagnosed with the autoimmune disease, Sjogren's syndrome in 2011 and took six months off from the game.

The condition saps her strength, meaning she must manage her game more than ever. She and Serena both had to win twice Friday because of rain postponements earlier in the week, something Serena says surely affected her sister's condition.

"I mean she'll never admit it, ever, but I don't think she was 100 percent," Serena said. "But you will never get that out of her, and quite frankly, three matches for her is much tougher than three matches for me."

That showed on Saturday.

Serena surged to a 4-0 lead over her big sister and won the first set in 22 minutes. Venus Williams, who withdrew from her previous event because of back problems, picked up her game a bit in the second set but it was hardly enough.

The match ended when Venus mishit Serena's final serve, and the sisters simply shook hands at the net when it was over, neither looking overly pleased. Serena waited until her sister left the court before to cheers talking with an on-court interviewer and giving the crowd a few comments.

Venus said dealing with this defeat won't be different than any other in her long career. She said she had her chances to succeed and couldn't do it, simple as that.

"We both had racquets and everything. I didn't take advantage of my opportunities, so there's no reason for me to be upset" at Serena, Venus said. "I just have to improve my game."

Still, Venus Williams was smiling when she walked into the packed stadium court for warm-ups. She jumped on Serena's first serve immediately to win the first point - and it was largely downhill after that.

Serena's powerhouse serves and accurate groundstrokes rarely gave Venus room to move. Serena regularly delivered serves in excess of 100 mph that Venus couldn't handle.

Serena Williams won the final game of the first set at love, and Venus looked out of options about how to break through.

When Venus did have a chance to tighten up the second set, Serena made sure it didn't happen.

Venus won two points on Serena's serve trailing 3-2 in the second set. Serena Williams won the next two points with serves of 107 mph and 108 mph. She followed that with ace off a 117 mph serve that Venus looked at before changing sides. Serena quickly ended the game a point later to regain control.

Venus was happy with her week, if not how she played against Serena. "You know, I've been off balance for a long time and I'm trying to regain my balance," she said.

Jankovic dropped a second-set tiebreaker and trailed 2-0 to Voegele. But the former No. 1 took the final six games to advance.

Jankovic has won four of nine career matches with Serena Williams, including a victory in Rome in their last meeting on clay in 2010. She understands Williams is playing at a very high level right now.

"But I'm going to go out there and try to play my best tennis and try to go for it," Jankovic said. "I have nothing to lose, and it's a great occasion. It's the finals."

• Read more articles by PETE IACOBELLI

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