 While living in Bombay in 1877, he started playing club rugby with Ponsonby in Auckland, even though the club was based well north of Bombay.Warbrick played well enough for Ponsonby to earn selection for Auckland Provincial Clubs (now Auckland) that year despite being only 15 years old.Playing at fullback for them against Otago, he became the youngest person to play first-class rugby in New Zealanda record he still holds .