Top seed and title favourite Novak Djokovic had to dig deep into his reserves to fend off a determined Radek Stepanek and reach the third round at Wimbledon.
A win against Andy Murray and run to the semi-finals at the Aegon Championships at Queen's Club marked Stepanek down as a player in form on grass, and he tested Djokovic close to the limit.
Eventually the Serbian found a way to beat perhaps the most dangerous of the unseeded players in the draw, coming through 6-4 6-3 6-7 (7/5) 7-6 (7/5) on Centre Court.
Stepanek slipped twice in the fourth-set tie-break to give up the early advantage, which he clawed back but then handed straight back to Djokovic.
At 5-2 it looked all over, but Stepanek had trailed by the same margin in the third-set tie-break and remarkably, taking successive points off his opponent's serve, he got back on level terms again.
Yet a volley into the net handed Djokovic a match point behind his own serve, and when the 2011 champion went across court with a forehand Stepanek feared the worst as it landed.
The ball was called out by a line judge, but Djokovic challenged that verdict immediately. Stepanek, engaging in the mild farce he peppered the match with, got down on his knees, hands clasped together, to offer a prayer.
But there was no salvation for the 35-year-old Czech, who reached the quarter-finals in 2006, as Hawk-Eye showed the shot had clipped the outside of the line for a clean winner.
The pair embraced warmly at the net and Stepanek's hope of an upset was gone.
Djokovic said: "I was two sets up and had some break-point chances in the third and I should have closed it out in the third set tie-breaker, but credit to him for fighting.
"He's 35 years old but he's moving very well. Grass is probably his most preferred surface. H e performs really well on the big stages as you saw.
"He loves to engage the crowd, he's an entertainer, and it was fun from one side to be part of a great thrilling match, but on the other side I should not have complicated my own life this way.
"It was annoying I came to Wimbledon without any official match practice and my first-round match went just over hour, so I didn't have a lot of match play.
"I was quite focused and tense before the match because I knew what was on the other side of the net. I knew his ability and his quality.
"It was a difficult one but I'm glad I stayed hanging in there mentally and managed to win."