LONDON (Reuters) - Chelsea coach Thomas Tuchel hailed new striker Romelu Lukaku for providing the missing piece in his team, who last year struggled to turn dominance of matches into goals even as they battled their way to Champions League success.

Lukaku scored in his first match back at Chelsea to set the Blues on their way to a 2-0 win at Arsenal as he dominated the Gunners' defenders throughout the 90 minutes.