Paris St Germain took a big step towards reaching the Champions League final as Ousmane Dembele's early goal sealed a 1-0 win at Arsenal in a tense first leg of the semi-final on Tuesday, Reuters reported.

Dembele fired home off the post in the fourth minute as PSG dominated the opening stages and Luis Enrique's side held firm to take a precious advantage back to the French capital.

Arsenal, playing in the semi-final for the first time since 2009, improved after a lacklustre start and had a Mikel Merino goal ruled out after the break while PSG keeper Gianluigi Donnarumma made several fine saves.

PSG weathered the storm and should have given themselves a bigger cushion for the second leg but Bradley Barcola and Goncalo Ramos both squandered gilt-edged chances late on, according to Reuters.