Hingis is going for her first title since returning to the tour

The pair were playing for the 21st time, with 10 wins apiece, Williams having won their last encounter in Warsaw earlier this month.

A repeat looked on the cards when Williams took the first seven games but Hingis came back to win 0-6 6-3 6-3.

Dinara Safina earlier won a marathon battle 3-6 6-4 7-5 against fellow Russian Svetlana Kuznetsova.

Safina, seeded 16, fought back after losing the first set to win in two hours 30 minutes.

I feel like I was capable of winning that match Venus Williams

"It was really a long time. In the second set I just said to myself 'play it point by point' and in the end it went my way today," said Safina.

Hingis beat Williams on her way to winning the title in 1998 and admitted her latest run to the final was an emotional affair.

"In the first set I felt like I could cry - I was missing my shots by a little bit and my timing was out," said the Swiss.

"It's amazing that I played Venus in the semi-finals again eight years later. I'm just trying to enjoy it.

"Rome has always been a special place for me and I'm happy to have made another final."

Williams said: "Obviously, I'm disappointed. I feel like I was capable of winning that match.