Aged 16 years and 361 days, the forward netted in the 10th minute of stoppage time to seal a dramatic 3-2 win at Newcastle United and set a new club record.
His effort meant he bettered the Reds' previous best held by Ben Woodburn, who was on the scoresheet against Leeds United in November 2016 when 17 years and 45 days old.
Ngumoha arrived at Liverpool last September and became the second-youngest appearance-maker in the club's history at the beginning of 2025.
He started an Emirates FA Cup tie with Accrington Stanley at Anfield, taking the Reds' record for youngest debutant in the competition as well.
And on Monday, teenager came off the bench late on at St. James' Park to make his Premier League debut and then, incredibly, netted a late, late winner.