Top-seeds Novak Djokovic and Serena Williams got their Wimbledon campaign off to a winning start on the opening day with straight-set victories.

Djokovic saw off Philipp Kohlschreiber of Germany 6-4, 6-4, 6-4, while Serena dusted off a few cobwebs as she survived an early wobble against Russian qualifier Margarita Gasparyan to win 6-4 6-1.

Serbia's defending champion, who won the Australian Open this year and then lost in the French Open final, is the man to beat at the All England Club again this year.

The top-seed won his second Wimbledon title last year, and came into this year's tournament with a 41-3 record.

Results (selected):

1-Novak Djokovic (Serbia) beat Philipp Kohlschreiber (Germany) 6-4 6-4 6-4
17-John Isner (U.S.) beat Go Soeda (Japan) 7-6(5) 6-4 6-4
24-Leonardo Mayer (Argentina) beat Thanasi Kokkinakis (Australia) 7-6(7) 7-6(3) 6-4
9-Marin Cilic (Croatia) beat Hiroki Moriya (Japan) 6-3 6-2 7-6(4)
26-Nick Kyrgios (Australia) beat Diego Schwartzman (Argentina) 6-0 6-2 7-6(6)

Serena has won Wimbledon five times [Getty Images]

Serena, meanwhile, made an inauspicious start to her bid for a sixth Wimbledon title and a second non calendar year grand slam when the lowly ranked Russian broke in the opening game and held on bravely as Williams slowly warmed up. 

The frustration was clearly telling on the American as she trailed by a break and 3-2 in the opening set, an audible obscenity earning her a warning from the umpire.

She received little respite from Gasparyan, whose rasping groundstrokes frequently found their target, but Williams discovered her rhythm, broke to level for 3-3 and did not look back.

The 33-year-old broke again when Gasparyan netted a backhand to clinch the first set after 48 minutes and powered away, breaking twice in the second set and crunching away a smash on match point to clinch victory.

The 2004 champion Maria Sharapova also moved into the second round with a 6-2, 6-2 win over Johanna Konta of Britain.

In seven of the past eight years, Sharapova has failed to reach the quarter-finals at the All England Club.

Results (selected):

4-Maria Sharapova (Russia) beat Johanna Konta (Britain) 6-2 6-2  
Aliaksandra Sasnovich (Belarus) beat Zhu Lin (China) 4-6 7-5 6-1
Jelena Ostapenko (Latvia) beat 9-Carla Suarez Navarro (Spain) 6-2 6-0
7-Ana Ivanovic (Serbia) beat Xu Yifan (China) 6-1 6-1
1-Serena Williams (U.S.) beat Margarita Gasparyan (Russia) 6-4 6-1
Zarina Diyas (Kazakhstan) beat 24-Flavia Pennetta (Italy) 6-3 2-6 6-4
11-Karolina Pliskova (Czech Republic) beat Irina Falconi (U.S.) 6-4 4-6 6-1
23-Victoria Azarenka (Belarus) beat Anett Kontaveit (Estonia) 6-2 6-1

Source: Al Jazeera and agencies