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.

Holder Barcelona put itself in the driving seat with a resounding 4-1 over Chelsea in the first leg of its women’s Champions League semifinal on Sunday, with substitute Claudia Pina netting twice.

The match began with intensity at the Estadi Johan Cruyff. In the 10th minute, Alexia Putellas had a chance to put Barcelona ahead from the penalty spot, but her shot was saved by goalkeeper Hannah Hampton.