Mikel Arteta has called Villarreal boss Unai Emery 'the most successful manager' left in the Europa League as the pair prepare to go head-to-head in the semi-finals.
Arsenal secured a place in the semi-finals by beating Slavia Prague 5-1 win on aggregate thanks to a 4-0 second-leg victory on Thursday night. While Villarreal progressed through to the final four after beating Dinamo Zagreb 3-1 on aggregate.
The Arsenal boss says it will be 'tough' to beat Emery - who managed the Gunners before Freddie Ljungberg's reign and his own arrival.
Arteta refers to Emery as the most successful manager - having previously won the Europa League three times with Sevilla - but insists his side have a 'real desire to improve' on their quarter-final performance.