Mets pitcher Noah Syndergaard will be sidelined through at least the All-Star break because of a torn muscle behind his right arm.

The hardest-throwing starting pitcher in the major leagues with an average fastball velocity of 98.7 mph this year, partially tore his latissimus dorsi against Washington last Sunday. The 24-year-old right-hander has been told not to throw for about six weeks and he will need a long period to build up arm strength again, equivalent to a full spring training.

"It stings,'' Syndergaard said Saturday, two days after he was examined in Los Angeles by Dr. Neal ElAttrache.