Complex sentence: Lambert continued to play for Arsenal over the next few years, scoring regularly; his five goals in a 9--2 defeat of Sheffield United remains the most ever scored by an Arsenal player in a single home match.
Split into simpler sentences: Lambert continued to play for Arsenal over the next few years, with regular goalscoring. These scoring feats included five goals netted in a 9-2 defeat of Sheffield United, the most ever scored by an Arsenal player in a single home match.