On 28 December 1998, Armstrong scored a late hat-trick in a 4–1 home win over Everton, and when he was substituted at the end of the game his teammate David Ginola got in his way to bow down to him. He scored five times in their League Cup run that season, including two in a 3–1 win over Manchester United in the quarter-finals, but was unused in the final at Wembley Stadium which Spurs won over Leicester City.