Joe Marler's dangerous shoulder puts his Six Nations campaign in doubt

Harlequins front rower Joe Marler will be in doubt for this year's Six Nations campaign after he received a straight red card in Saturday night's Aviva Premiership clash with Sale Sharks, which the latter edged 30-29 after a late referee decision.  Harlequins were 22-17 up when the England prop dropped his shoulder into Sale Sharks flanker TJ Ioane, leading to referee Matt Carley dismissing him from the field.  "That's the part of the game we need to take out, where someone's defenceless and you can knock them with your shoulder," said Sale Sharks' Steve Diamond.  Harlequins director of ru…