Already bereft of the two most decorated men’s players of the past decade, Roger Federer and Rafael Nadal, Wimbledon came precariously close to losing the hope of Britain on a dreary Wednesday afternoon.

But after falling behind two sets to none, Scotland’s Andy Murray, the tournament’s No. 2 seed and overwhelming crowd favorite, rallied to halt an inspired charge by unseeded Fernando Verdasco of Spain, 4-6, 3-6, 6-1, 6-4, 7-5.

With the victory, Murray advanced to Friday’s semifinals and a date with the self-proclaimed world’s happiest person, Jerzy Janowicz of Poland, who wept with joy upon defeating younger countryman Lukasz Kubot. Kubot ran around the net to congratulate Janowicz, crumpled on the grass, and the two shared a long embrace, then exchanged shirts as soccer players do.

“He’s my Davis Cup mate,” Janowicz said of Kubot following his 7-5, 6-4, 6-4 victory. “He’s my good friend.”

Friday’s other men’s semifinal promises a reprise of the 2012 Olympics bronze-medal match, pitting Wimbledon’s 2011 champion and top seed, Novak Djokovic, against Argentina’s Juan Martin del Potro.

Nearly one year ago, the hard-serving del Potro defeated Djokovic, Serbia’s Olympic flag-bearer, for bronze.

On Friday, Djokovic will be favored. But neither player has lost a set en route to the semifinals — a stunning achievement over five rounds of best-of-five-sets tennis.

Del Potro’s campaign to reach Wimbledon’s semifinals appeared over almost as soon as it started, with the Argentine taking a nasty fall early in the first set against Spain’s David Ferrer. Del Potro opened the match with mummy-like taping on his left knee, which he hyperextended during a bad tumble earlier in the tournament. He lay motionless for a troubling length of time, explaining later that it was more out of fear than acute pain.

With a dose of anti-inflammatories, he played on, unloading the full force of his 6-foot-6 frame on his serve and forehand. It was too much for the 5-9 Ferrer, one of the sport’s more tenacious fighters. Del Potro prevailed, 6-2, 6-4, 7-6 (7-5).

Djokovic and seventh-seeded Tomas Berdych of the Czech Republic delivered the afternoon’s best single set of tennis to open their match. It was rife with exceptional shot-making and settled by a tiebreak, which Djokovic claimed on an overcooked forehand blast by the Czech.

Berdych broke twice to take a 3-0 lead in the second set. But Djokovic roared back, reeling off the next four games and never relinquishing control from there to move on, 7-6 (7-5), 6-4, 6-3, to his 13th consecutive Grand Slam semifinal.

Murray was the only semifinalist pushed to five sets. Though his 8-1 career mark against Verdasco suggested a lopsided match, it was anything but.

Ranked No. 54 in the world, the left-handed Verdasco ran Murray ragged by painting the sidelines with sharply angled groundstrokes. And he put one of the game’s better returners on the defensive with thunderstruck serves.

After dropping the first set, Murray bolted to a 3-1 lead in the second set only to let it slip away. In arrears by two sets, the Scot unleashed a vulgar tirade of self-loathing during the changeover that followed.

It helped, as did the outpouring of encouragement from the Centre Court faithful.

Murray bolted to a 3-0 lead in the third set, which he closed without surrendering a single point on his serve in the final game.

The fourth set was a nail-biter, with both players racing and diving from one side of the court to the other to keep the ball in play.

Murray faced such a long road back that the crowd celebrated every break point as if a triumph.

“This is thrilling and nerve-racking in equal measure!” exclaimed the BBC’s Sue Barker when Murray finally broke serve to pull ahead in the fourth set.

The Scot served out the tight fifth set at love, as well, looking more relieved than jubilant.