Warren Gatland denies Johnny Sexton is trailing Owen Farrell in Lions stakes

• ‘That’s pretty unfair in making an assessment like that,’ head coach says• Johnny Sexton struggles in tour opener and replacement Farrell plays key roleWarren Gatland has insisted it would be unfair to write off Johnny Sexton’s challenge for a British & Irish Lions Test shirt after a wretched night in Whangarei, when the Ireland fly-half Sexton struggled and Owen Farrell stepped off the bench to help salvage a 13-7 victory, overturning a 7-3 half-time deficit.Gatland hailed Farrell’s big-match temperament in digging the Lions out of a hole after he initiated the play that led to Anthony …