With manager Marco Silva without several of his key players because of international commitments, this was a huge victory for Fulham.
With Alex Iwobi, Calvin Bassey and Samuel Chukwueze spending the month representing Nigeria at Afcon, the Cottagers were missing a trio who had started a collective total of 34 out of a possible 48 games in the Premier League this season.
But when Kevin, making just his fourth start of the league campaign, raced past the Forest defence and whipped a delightful ball across the face of goal within the first 30 seconds, it was clear Fulham were out to show they were more than capable of securing victory in the absence of their key men.
On the night, it was the unpredictability of Kevin and the experience of left-back Antonee Robinson that spurred the Cottagers to victory.
Brazil youth international Kevin, who arrived from Shakhtar for a club record £34.6m in September, was lively throughout his 78 minutes of action before being replaced by King, with his trickery and close control drawing a foul from Luiz in first-half stoppage time to earn the decisive spot-kick for his side.
At 22 years old, it is only natural that the wide forward has plenty to learn and improve upon, his decision-making in particular, but this outing is one that will provide plenty of excitement for Fulham fans, particularly when they are without Chukwueze.
With Brazil's assistant manager Clement in attendance, Kevin's performance could give the national coaches something to think about before next summer's World Cup.
In the meantime, he is likely to have plenty more opportunities to impress in the Premier League until Chukwueze returns from international duty.