The world number three eventually saw off South Korea's Kwon Soon-woo in five sets
Novak Djokovic's defense of his Wimbledon crown began with a hard-fought win after the Serb beat Kwon Soon-woo 6-3, 3-6, 6-3, 6-4 on Monday.
Djokovic's world number 81 rival gave him an early scare by going up 3-1 in the first set before then losing five consecutive games to the all-time great.
In the second set, with Soon-woo winning 1-0, the match had to be temporarily suspended for the first time as a spectator was taken ill and four medics had to rush to the fan's aid.
Play resumed after five minutes, but it needed to be paused on a second occasion as an older punter had to be helped in a separate medical emergency.
Soon-woo eventually went on to take the second set 6-3 after the scares had passed, which represented the second year in a row that 2021 champion Djokovic had dropped a set in the first round.
Proving too much for his 24-year-old opponent, however, Djokovic went on to take the third and fourth sets 6-3, 6-4 and advanced to the second round to keep his dreams of being the fourth man to win a fourth consecutive title at the All England Club alive.
Both men received applause from the SW19 crowd, and for Djokovic the victory was historic as it meant he became the first player, male or female, to win 80 singles matches across tennis' four Grand Slams.
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