Liverpool secured a vital advantage over Arsenal in the battle for a place in the Premier League's top four with a well-deserved win at Anfield. Arsenal manager Arsene Wenger gambled by leaving Alexis Sanchez - his leading scorer with 17 Premier League goals - on the bench but the ploy failed miserably as Liverpool took control by the break. Roberto Firmino's far-post finish put Liverpool ahead after nine minutes and Sadio Mane confirmed their superiority with an emphatic strike just before half-time.