Having seen Rafael Nadal fall victim to a thrilling five-set upset yesterday, Djokovic suffered no such problems to progress into the next round with a 6-2 7-6(5) 6-4 triumph in just over two hours.
The Serb quickly took control of the opening set to race into a 3-0 lead and, while Mannarino saved two break points to avoid things becoming even worse, he struggled to make any headway on the Djokovic serve.
Djokovic needed three set points to finally put the Frenchman away in the first set, though, eventually claiming it 6-2.
The second set got off to an identical start as Djokovic once again stormed into a 3-0 lead, but this time Mannarino was able to fight back and claimed a break of his own to force a tie-break.
None of the opening five points went with the serve, but Djokovic recovered from 4-2 down to take it 7-5 and leave himself in complete control of the match.
Another early break followed in the third, and that proved to be all the three-time Wimbledon champion needed as he wrapped up a 6-4 win to set up a quarter-final showdown with Tomas Berdych.