The 19-year-old scored his first Premier League goal for the Reds at the Kop end to help them towards a convincing victory over their struggling visitors, with Philippe Coutinho, Roberto Firmino (2) and Alex Oxlade-Chamberlain also getting on the scoresheet.
It was also Alexander-Arnold's first Anfield goal, and the youngster revealed that he had family members in attendance to witness the moment.
"It's a dream come true to score at Anfield, especially to win. I've scored two goals away from home but it's good to get one at Anfield, especially at the Kop. I had a few family members here," he told Sky Sports News.
"[Manager Jurgen Klopp] was really happy with the goal. I got an elbow to the face at one point and he said I had to get back up unless I had a broken nose. The performance could have been better, especially in the first half."
The victory lifts Liverpool back into the top four of the Premier League table heading into their final match of 2017, which sees them host Leicester City on Saturday.