(REUTERS) - World No. 1 Simona Halep swatted aside American Nicole Gibbs while Maria Sharapova was flawless in her straight sets victory over Romania's Mihaela Buzarnescu in the opening round of the Shenzhen Open on Monday (Jan 1).

Halep, who sealed a 6-4, 6-1 victory, struck three aces and fired 12 winners and was at her aggressive best to set up a second-round clash with China's Duan Yingying who defeated Evgeniya Rodina 6-2, 7-5.

"It's always nice to play here in Shenzhen," said Halep, who captured the Shenzhen Open title in 2015.

"It's my first victory this year as number one in the world, so I'm happy and enjoying the time."

Five-time Major winner Sharapova hit 18 winners and needed one hour and 22 minutes to dispatch the seasoned Buzarnescu 6-3, 6-0 for a winning start to the year.

"Every match gets tougher and as a competitor and someone who tries to be realistic, I like to only look ahead to the next opponent," Sharapova said after the match.

The Russian next faces 2017 Shenzhen Open runner-up Alison Riske, who upset China's fifth seed Wang Qiang on Sunday.

"She beat a crowd favourite yesterday so I know I have a tough match ahead, but I just want to keep playing better, and keep improving no matter who is across the net."

Unseeded Danka Kovinic, ranked 123rd in the world, stunned Greek seventh-seeded Maria Sakkari 4-6, 6-2, 6-3.

Local hope Zhang Shuai powered past Russia's Anna Blinkova 6-3, 6-4 and was joined in the next round by Timea Babos who beat China's Wang Xiyu 6-1, 6-1.