Holders Barcelona put themselves in the driving seat with a resounding 4-1 over Chelsea in the first leg of their women's Champions League semi-final on Sunday, with substitute Claudia Pina netting twice.

UEFA Technical Observer Anna Signeul highlights how the second-half introduction of Barcelona substitute Clàudia Pina proved crucial in her side's 4-1 victory over Chelsea in the first leg of their UEFA Women's Champions League semi-final.

The striker sustained a left hamstring injury on Saturday. He is Barcelona's top scorer this season with 40 goals in 48 games.