Goffin will wonder just what happened after he looked the better player in the early stages and broke for a 4-3 lead in the first set, Reuters reported.
Half an hour later he had lost 10 games in a row and the match was effectively over as Djokovic, relentless with his accuracy, went on to triumph 6-4, 6-0, 6-2.
It was a display of Djokovic at his clinical best as the Serb soaked up the early punches without panic then slowly but surely imposed himself in every aspect of the contest to such an extent that Goffin was left flailing.
Djokovic, who has lost only once at a Grand Slam in the last 12 months, is into his ninth Wimbledon semifinal – only Jimmy Connors and Roger Federer have been in more
Defending champion Novak Djokovic is the first man to reach the Wimbledon semi-finals after breezing past David Goffin in straight sets.
"He started well. He was dictating the play from the baseline," Djokovic told the BBC.
"Things could have gone a different way, who knows what the match would have looked like if I had lost the first set but I was very pleased with the second and third.
"I had a tough match in the third round. Other than that, I've won in straight sets and played really well throughout the tournament.
"It's exactly what I wanted and hopefully I can go in the right direction in the semis as well."