NEW YORK :United States two-time World Cup winner Tobin Heath announced her retirement on Thursday, after years away from the sport due to injury, disappointing her legions of fans who hoped she might one day retake the field. Famed for her cool demeanour and extraordinary intelligence on the pitch, Heath picked up two Olympic golds and won the NWSL championship twice with the Portland Thorns. "I think I had a few more mountains I wanted to climb with football, even though I'm really grateful