Champion Djokovic rebounds in Rome

(CNN) -- Defending champions Novak Djokovic and Maria Sharapova came through second round matches at the joint ATP/WTA tournament in Rome Tuesday with straight sets victories.

Djokovic was in blistering form under the lights at the Foro Italico and saw off Australian teenager Bernard Tomic 6-3 6-3 in an entertaining encounter.

The world number one was coming off a shock defeat to compatriot Janko Tipsarevic in Madrid last week on the notorious blue clay, but an upset never looked likely against Tomic.

Djokovic quickly moved two breaks ahead in the opener before Tomic made a spirited recovery to achieve a break of his own.

It only delayed the inevitable as Djokovic broke him again to close out the first set.

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A single break of service decided the second set with the Serbian always in command as he wrapped up victory in 68 minutes.

Their match had followed a classic encounter between fourth seed Andy Murray and Argentina veteran David Nalbandian.

Murray, who missed Madrid through injury, breezed through opener 6-1 but Nalbandian hit back to level by taking the second set 6-4.

When he broke Murray in the decider an upset looked on the cards, but the Scot rallied and pulled ahead at 6-5 courtesy of a fortunate net cord.

Nalbandian forced two break points as Murray served for the match, but both were saved and the Murray, on his 25th birthday, clinched a hard-fought victory after two hours 38 minutes.

Earlier, Sharapova, the second seed on the red clay in the Italian capital, had fought off a tenacious challenge from American Christina McHale.

She won 7-5 7-5 but trailed in both sets, including coming from 4-1 down in the opener.

She finally prevailed after two hours 12 minutes to keep the defense of her title on track.

"I made too many unforced errors in the first part of the match and she was playing extremely consistently," the Russian told the WTA Tour website.

"Maybe I was trying to hit too many winners then. But I was fortunate enough to win that first set and get back into it in the second set."

Improving on the surface, Sharapova has won 17 of her last 19 matches on the surface, taking the title at Stuttgart earlier this year.

Wimbledon champion Petra Kvitova also progressed to the third round, but like Sharapova, was pushed over two sets against Russia's Anastasia Pavlyuchenkova before winning 7-5 6-4.

The pair had shared their previous four meetings, but fourth seed Kvitova showed she is adapting better to clay to go through after retrieving early deficits in both sets.

The Williams sisters also progressed, with Madrid champion Serena next facing Russia's Nadia Petrova in the second round on Wednesday.

The America, seeded ninth, won the tournament 10 years ago.

Her older sibling Venus beat Romania's Simona Halep in the first round for the second tournament in a row, and the 1999 Rome champion will take on Russia's Ekaterina Makarova as she seeks to improve on her second-round defeat on the blue clay last week.