Lions must keep discipline but show their intent, says Johnny Sexton

• Fly-half sees second Test link with how All Blacks gained revenge over Ireland• Andy Farrell: you don’t just win the game by being raging madThe British & Irish Lions are being warned not to lose their heads amid the intensity of the second Test against New Zealand. The touring team are primed for a highly physical all-or-nothing encounter but their fly-half, Johnny Sexton, and the defence coach, Andy Farrell, are also stressing the need for discipline.Sexton sees some similarities with last November when New Zealand thundered into Ireland in Dublin after losing to the same opponents in …