Replays were not immediately conclusive as to whether or not the ball had already crossed the goal-line prior to Sterling's intervention.
At full time, BT Sport's Jake Humphrey congratulated Sterling on becoming the first player to score a hat-trick in an FA Cup final since 1953.
Sterling, who scored two indisputable goals late in the second half, replied to Humphrey: "You're bantering me. That's sh*t from me then… poor from me! I didn't mean to do it. I'm sorry."