The last four teams standing return to play in the UEFA Champions League this week for the first leg of the semifinals, when some of Europe's top sides will begin to map out their route to the final on May 31 at Munich's Allianz Arena.

Arsenal beat PSG 2-0 earlier this season when the two sides met at Emirates Stadium in the league phase of the Champions League. The two clubs meet again in the first leg of their semi-final and Enrique insists his side have made huge strides since then.

Merino missed the Gunners’ most recent match - against Crystal Palace last Wednesday - and was a doubt for the first leg of Arsenal’s semi-final against PSG at Emirates Stadium on Tuesday. The Spaniard, however, took part in training on Monday afternoon and is expected to be fit for the game.