A floodlight failure and a raft of enforced changes could not derail Leicester as they began their defence of the FA Cup with a convincing 4-1 win over Watford.
Youri Tielemans and James Maddison got the Foxes off to a fine start in their third-round tie at the King Power Stadium before Harvey Barnes and Marc Albrighton struck after a Joao Pedro reply.
The lights went out for a short period early in the second half as the Foxes led 3-1, and Pedro hit the bar soon after the restart, but the hosts finished the stronger.
It was a lively encounter, despite managers Brendan Rodgers and Claudio Ranieri making a combined 16 changes between them.
Hampered by a lengthy injury list and Africa Cup of Nations call-ups, Leicester accounted for nine of those alterations with just Maddison and Hamza Choudhury surviving from the side that beat Liverpool on 28 December.
Yet with the likes of Maddison, Tielemans and Barnes on the field, the Foxes were still favourites against a Watford perhaps more concerned about some crunch relegation battles in the weeks ahead.
Former Leicester boss Ranieri retained just four players from the side beaten by Tottenham on New Year's Day and decided not to risk top scorer Emmanuel Dennis or new signing Samir. Another recent recruit, Hassane Kamara, only made the bench.
Leicester were gifted the perfect start when referee Mike Dean pointed to the penalty spot after ruling that Francisco Sierralta pulled down Jannik Vestergaard.
There was a delay as VAR checked the decision but Tielemans, who scored the winner in last season's final, was not unnerved as he stroked into the bottom corner from 12 yards.
Watford responded well with Tom Cleverley having a shot blocked by Choudhury and Moussa Sissoko firing over but Leicester went close again when Barnes drilled a ball across goal.
Vestergaard then headed over at a corner before the hosts doubled their lead after 25 minutes as Ademola Lookman turned and played in Maddison, who finished with a clever dink over Daniel Bachmann.
Again Watford reacted positively and they pulled themselves back into the game almost immediately as Ashley Fletcher slid in Pedro and the Brazilian lifted over Danny Ward in similar fashion to Maddison moments earlier.
After a quiet ending to the first half, Leicester were revitalised by the break and restored a two-goal lead with 54 minutes gone.
Lookman was again the provider from the left and Barnes raced through to finish sweetly past Bachmann.
His celebrations were initially cut short by an offside flag but his efforts were rewarded as the goal was allowed to stand following a VAR review.
It was at this point the floodlights went off, plunging the ground into near-darkness. Fans took it in good humour by shining their own lights and singing "we'll play in the dark" as the players moved to the side of the pitch for impromptu team talks.
The matter was soon resolved and play resumed after a delay of around six minutes.
Watford fought on and Pedro went close to claiming a second with a shot that was deflected onto the bar.
Leicester, however, put the game beyond doubt with five minutes of the original 90 remaining - although there were to be nine minutes added on.
Lookman produced a brilliant save from Bachmann at point-blank range but Albrighton was on hand to blast home the rebound.