Novak Djokovic extended his recent dominance over Rafael Nadal by rallying for a 4-6, 6-3, 6-3 victory Sunday to win the Italian Open for the third time — then dedicated the title to his flood-hit native Serbia.

Having also been beaten in Monte Carlo and Barcelona recently, it marked the first time in a decade that the top-ranked Nadal has lost more than two matches on clay in the same year.

In the women's final, Serena Williams kept the crowd from being a factor in a 6-3, 6-0 victory over 10th-seeded home favourite Sara Errani to win her third Rome title.

Errani was bidding to become the first Italian to win the tournament in nearly 30 years but the top-ranked Williams quickly took control in both sets and Errani appeared slowed by a left thigh problem.

Djokovic carved a heart on the clay with his racket to celebrate his title.

"This heart on the court is for you," he told the fans in Italian during the victory celebration. "It's also a special dedication to my country, which is suffering a lot right now. My heart is with them."

Authorities say 25 people have died in the Balkans because of the worst flooding in a century after three months' worth of rain fell on the region in three days this week. Tens of thousands of homes were left without electricity or drinking water.

The second-ranked Djokovic has now won four straight matches against Nadal — the previous three in straight sets — and takes the psychological edge into the French Open, which starts next weekend.

Roland Garros is the only Grand Slam that Djokovic has yet to win, with his best result a runner-up finish in 2012. Nadal has won the French Open eight times.

Djokovic's other Rome titles came in 2008 and 2011.

Decisive break

Midway through the final set, Djokovic earned a decisive break as Nadal made several uncharacteristic errors, and then broke again to close it out.

In the final game, Djokovic blasted a backhand cross-court return winner right by Nadal, before a backhand from the Spaniard sailed long on the second match point.

Djokovic, who sat out last week's Madrid Open due to a right wrist injury, hit 46 winners to Nadal's 15, while the unforced errors column was nearly even with Djokovic committing 30 and Nadal 27.

Djokovic's serve was also a factor. He hit six aces while Nadal had none.

Nadal was pushed to three sets in four out of his five matches here.

"It was a difficult week," the Spaniard said. "Too many hours on the court."

Earlier, Errani left the court for an injury timeout while trailing 5-3 in the opening set and came back with her thigh bandaged. On the final point before she left the court, Errani pulled up and let a shot from Williams pass by her without even attempting to get to it.

"I'm sorry. You were unbelievable all week," Errani told fans during the victory ceremony, as she brushed back tears. "I tried to do my best and stayed on the court only for you."

Williams' other Rome titles came in 2002 and last year — and she went on to win the French Open on both occasions.

"I'm also sorry for Sara today," Williams told the crowd in Italian. "She really played great all week."

A left thigh problem prompted Williams to withdraw before her quarterfinal match at the Madrid Open last week but now she appears back on track for the French.

"I'm not 100 per cent but I'm just kind of going on adrenaline," Williams said.