DOHA, Qatar - Gisela Dulko and Flavia Pennetta put the finishing touches on their dynamite doubles season on Sunday night, beating Kveta Peschke and Katarina Srebotnik, 75 64, for their biggest career title in Doha.

Dulko and Pennetta, already winners of six titles this year and the No.1 seeds at the prestigious season-ending WTA Championships - Doha 2010, faced set point at 4-5 in the first set, but Pennetta conjured up a strong first serve that drew a forehand return error from Peschke; Dulko and Pennetta then went on an eight point tear, winning the next two games at love to tuck away the first set.

The second set stayed on serve until the fifth, sixth and seventh games, all of which were breaks - with Srebotnik, Pennetta and Peschke all losing serve. But Dulko never did, leaving the No.1 seeds up a break the rest of the set - Pennetta served it out, building a 40-0 lead and cliching it on the second match point.

"It feels amazing," Dulko said. "When we started playing together this year, we never thought we would end the year like this. We're very proud of the hard work we've put in. And to share this with Flavia is very special - we started playing doubles because we are best friends, and the happiness is double."

"We just started playing together because we are friends and love to play together and we never thought we would end up in this position," Pennetta said. "To have the chance to play a sport with one of your best friends is the nicest thing in the world. We are really happy and proud. We can't believe it yet."

Dulko and Pennetta were making their first career appearances at the WTA Championships - together and individually. On Saturday they were confirmed as the year-end No.1 team on the WTA; and to add to that, Dulko will rise to No.1 on the individual doubles rankings, just the second South American ever to achieve that feat (after Paola Suárez, who was also from Argentina).

Peschke and Srebotnik, who won titles this year at Indian Wells and New Haven and were the No.2 seeds this week, had both played the WTA Championships multiple times before - this was Peschke's fourth appearance (her best result being runner-up in 2008 with Rennae Stubbs) and Srebotnik's fifth appearance (her best result being runner-up in 2007 with Ai Sugiyama).

"We're very happy despite the loss today," Srebotnik said. "We felt this would be our title but we have to give credit to Gisela and Flavia, they played so well and no doubt deserve it. The better team won today. We are happy to have been in the final though - it was really a great achievement for us."