A first-half hat-trick from four-goal Sam Kerr and goal and assist from Lauren James were the highlights in a masterclass from Chelsea, who booked a place in the Continental Cup final against Arsenal by thrashing West Ham. Emma Hayes had said her players were “very, very clear about how hard it is going to be to score a goal against West Ham”, with Paul Konchesky’s side having dented Arsenal’s title aspirations by earning a 0-0 draw in the league at the weekend. They were perhaps as surprised as anyone, then, to take the lead in the fourth minute and be four goals up by half-time. Hayes made four changes to the side that was made to work hard for a 3-2 win over Tottenham on Saturday. Fran Kirby started, Magda Eriksson was back and returned to her more familiar centre-back berth, summer signing Eve Perisset was in and Ann-Katrin Berger was preferred to Zecira Musovic in goal. The opening goal exposed the West Ham back line, and they didn’t seem to recover. Guro Reiten’s free-kick was met by Kerr at the back post and the potent forward was allowed to wait for the ball to drop before firing a volley from close range while two defenders watched on. There was little West Ham could do about the second, though, as James tracked back, won the ball, then sent it curling around the defence and into the run of Kirby who slotted the ball past Mackenzie Arnold. There were errors again for the third, with Erin Cuthbert poking Emma Snerle’s loose pass towards Kerr who fired into the far corner. Kirby’s start was reduced to a first-half cameo, the forward forced off after going down holding her right leg while off the ball, but her absence didn’t disrupt the Chelsea momentum, with Jelena Cankovic coming on in her place. In added time at the end of the half it was four, with Hawa Cissoko losing her footing and allowing the ball to be poked into Kerr’s path for the Australian forward to secure her hat-trick. There were four half-time changes to the West Ham team that had earned the point against Arsenal, but still the Blues poured forward. James provided the fifth, cruising into the box on the left, cutting inside and hammering a powerful effort past Arnold. West Ham’s woes would extend beyond the scoreline, with substitute Lucy Parker forced off after 57 minutes with a leg problem. Five minutes after the fifth, Kerr had another, feeding Perisset out wide before heading home after the full-back returned it. Reiten would get in on the action not long after, turning and firing in after Cankovic found her in the middle with her back to goal. It was a scoreline not befitting a cup semi-final and for West Ham, although there could be some expectation that Saturday’s effort against Arsenal had taken its toll, professionalism should counteract that.