Rafael Nadal was forced to work for a first-round victory over Francisco Cerundolo on Centre Court at Wimbledon.
The world number two overcame a scare to secure a 6-4 6-3 3-6 6-4 win at SW19 despite making 41 unforced errors as he eyes a first calendar Grand Slam.
Second seed Nadal, who won his first grass-court match in three years in an exhibition match against Stan Wawrinka last week, secured a break in the fourth game but Argentine Cerundolo immediately responded, finishing with a strong overhead volley after the Spaniard lost his footing after his service.
Cerundolo was certainly not fazed by his all-conquering opponent, with the pair exchanging thrilling rallies and both displaying an array of brilliant shots in a first set that Nadal won by breaking for a second time.
The 22-time major champion made a scrappy start to the second set, but a solitary break in the sixth game put him one set away from round two.
In the third, Cerundolo continued to battle as he broke Nadal back immediately to peg him back at 2-2 and edged in front at 5-3 before serving out the set to raise hopes he could pull off a huge shock.
The world number 42 continued to excel as he opened up a 3-1 lead in the fourth set, but Nadal roared back and won 11 consecutive points, breaking twice to seal his spot in the second round without being taken the distance.
He will face Ricardas Berankis in the second round at the All England Club.
Data slam: Nadal matches Navratilova record
Nadal's victory saw him equal the great Martina Navratilova's record of 306 grand slam wins in his career.
That puts him joint-fourth on the all-time list, behind only Roger Federer (369), Serena Williams (365) and Novak Djokovic (328)
Nadal – 23/41
Cerundolo – 30/46
Nadal – 5/3
Cerundolo – 2/2
BREAK POINTS WON
Nadal – 6/14
Cerundolo – 4/18