CHARLESTON, S.C. (AP) — Venus Williams helped Washington catch up, then beat Coco Vandeweghe in a last-game tiebreaker as the Kastles completed their second straight undefeated championship WTT season with a 20-19 victory over Sacramento on Sunday.

The triumph capped a long, hard season for Williams, who has learned to compete while living with the auto-immune disease, Sjrogren’s syndrome, that kept her out of the game from September 2011 through last March.

Williams felt fit, confident and ready to dig in and do whatever it took to succeed.

“I really felt like I came out on fire in all my matches,” said Williams, named the WTT finals MVP.

Williams got plenty of work at the Family Circle Tennis Center to wrap up Washington’s second consecutive, 16-0 season and third title in four years.

She and teammate Anastasia Rodionova won the women’s doubles match to put Washington in front 8-6. After Sacramento took the men’s doubles match to lead 11-10, Williams and Leander Paes won the mixed doubles competition in a last-game tiebreaker and sent the championship into a final women’s singles showdown tied at 15-games apiece.

Vandeweghe broke Williams’ serve to lead 3-2, but Williams broke right back and the match eventually went to the WTT’s best-of-9 point, super tiebreaker. Vandeweghe quickly led 2-0 when Washington called time out. Paes jogged over talk with the seven-time Grand Slam champion.

“I just told her she’s one of the greatest of all time,” Paes said. “Go have fun and hit your shots.”

That’s what Williams did, winning the next five points including an ace down the middle to set up match point. Vandeweghe sent a final forehand long to start Washington’s celebration, Williams swarmed by teammates before doing her own little happy dance to the delight of the fans.

Just don’t mistake Williams’ moves for the “Crip Walk” steps little sister Serena did at the Olympics. “I have my own little combo,” Venus Williams said. “The Venus combo.”

Vandeweghe slammed her racket down in frustration on the final shot went long and the match ended. Vandeweghe was part of Sacramento’s mixed doubles team with Mark Knowles that lost that tiebreaker.

“You know, a lot of the times it comes down to missing one opportunity on a three-all point,” Vandeweghe said. “That’s what makes it fun to play World Team Tennis. Winning those opportunities is more fun than losing them.”

It’s been a long, challenging season for Williams, who returned to the tour in March after six months recovering from the diagnosis. She has dealt with fatigue and joint pain and learned the regimen to keep her healthy and playing high-quality tennis.

The 32-year-old Williams has struggled to find the singles form that won her five Wimbledon and two U.S. Open crowns. But she’s taken satisfaction, she says, in succeeding in group ventures, like teaming with Serena to won Olympic doubles gold in London and helping the Kastles to another WTT title.

“It’s my first World Team Tennis title in 12 years,” she said. “It’s amazing.”

And also a lot of fun for the competitors. Williams entered the past two nights with her dog, Harold, dressed in a dog-sized Washington warm-up shirt. Williams was off the bench cheering her teammates when she wasn’t on the court.

It took the Kastles some time to adjust, though. The tennis league typically wraps up in midsummer after a three-week long season. This time, organizers pushed it to September because of the Olympic tennis competition and the string of established tournaments leading up to the U.S. Open.

Paes said the team was out of synch on Saturday night as it rallied to defeat the New York Sportimes and John McEnroe for the Eastern Conference finals. He never doubted his club would end on top. “We find solutions. We always have in my four seasons here,” said Paes, the world’s fifth ranked doubles player who completed the career Grand Slam with a doubles title at the Australian Open last winter.

Williams as a big part of Washington’s solution this time around. She smiled wide as she posed with teammates on Billie Jean King Court, the venue re-christening its main court for the tennis icon last April. Williams was grateful for the victory and excited about what’s she’s accomplished, both on and off the tennis court.

“This whole year’s been a fight,” Williams said. “But for me, the year’s been incredibly successful because of what I’ve been up against.”