By NEALE HARVEY

Assessing his options: Quins lock James Horwill

Learning curve: Kyle Sinckler has been told to toe the line
PICTURES: Getty Images

HARLEQUINS skipper James Horwill has told hot-headed prop Kyle Sinckler to clean up his act if he is to fulfil the potential of becoming the best tighthead specialist on the planet.
Sinckler, 26, was a British & Irish Lions hero in 2017 and has been a mainstay of England’s forward effort since superseding Dan Cole during last year’s Six Nations championship.
However, disciplinary indiscretions continue to haunt the south Lon...