The Spaniard's pursuit of a hat-trick of world titles could not have got off to a better start with a hypnotic performance to Spanish guitar music Malaguena to earn 109.05, shattering his previous personal best by almost five points.
Fernandez's skills left the rest of the field trailing and Shoma Uno ended up being the best-of-the-rest, finally emerging from the shadow of his more illustrious compatriot, Olympic champion Yuzuru Hanyu, to finish second with 104.86.
The old-school style of Canada's Patrick Chan also won over the judges as he broke the 100-point barrier in an international meet for the first time to finish third with 102.13. He was the only competitor in the top six to attempt only one quad in the two-minute-40-second routines.
"I have been waiting to break the 100 at an (international) event," said the 26-year-old, who won a hat-trick of world titles before settling for Olympic silver behind Hanyu in 2014.
"To do it at worlds, just shows what I could potentially score if I did add a second quad."
Before the start of the competition, all the hype had been about the number of high-scoring jumps the 'Next Gen' of skaters were cramming into their programmes.
On Thursday, 20 of the 36 skaters had ambitions to execute the jump that requires four complete aerial revolutions before touch-down on the ice.
Of those, seven had included two quads in their short programmes.
American Nathan Chen, the first man in history to land four different types of quads (Lutz, flip, toeloop, Salchow) and five in total in his free skate at this year's U.S. Championships, has been seen practising six quads for Saturday's free skate in Helsinki.
He was flying high when he earned a whopping 19.47 points for his quadruple Lutz-triple toeloop combination, the highest score for a single element on Thursday. But the 17-year-old soon came back down to earth with a painful thud when he fell over on his triple Axel.
A score of 97.33 meant the Four Continents champion trailed in sixth place, 1.06 points behind Hanyu.
The Japanese favourite lost momentum after he misjudged his takeoff for his quadruple Salchow-triple toeloop combination and landed on a bended knee following the first jump.
Although that glitch left him 10.66 points adrift of Fernandez, Hanyu is not completely out of the running for gold and will be harbouring hopes of gaining revenge on his training partner.
Last year Fernandez, who like Hanyu is coached by 1987 world champion Brian Orser, overhauled a 12-point deficit from the short skate to snatch gold.
Fernandez, however, has no intention of giving up his crown.
"If I am able to come out on top when so many skaters produced such amazing routines, that gives me confidence," said the five-times European champion.
"I know I can stay here even when younger skaters are challenging me."
Chinese teenager Jin Boyang's crowd-pleasing routine to the Spiderman soundtrack earned him a personal best of 98.64, placing him fourth.
(Reporting by Pritha Sarkar, editing by Clare Lovell)
