Justin Rose admitted he lost to the better man as Jordan Spieth won his first Masters title in emphatic fashion. The 21-year-old finished 18 under to beat Rose and Phil Mickelson by four shots and become the second youngest Masters winner - after Tiger Woods in 1997. Spieth became only the fourth player after Jack Nicklaus, Ray Floyd and Tiger Woods to reach 17 under. Only Spieth and Wood ever got to 18 under, and Spieth is now the only person to reach 19 under. Jordan Spieth (right) receives the Green Jacket from last year's Masters winner Bubba Watson . Spieth celebrates becoming the second youngest ever Masters winner after his four-shot victory on Sunday . Justin Rose (left) congratulates Spieth after the young Texan holes his last shot on the 18th green . McIIroy shot an impressive last-round 66 but could only finish fourth behind Spieth, Rose and Phil Mickelson . Rose, who finished joint-second with Phil Mickelson on 14 under, said: 'Phenomenal, what a month of golf Jordan's had. Awesome composure; every time I thought there was a chink in the armour he would come out and hole an eight foot putt. 'Jordan seems to have that same quality right now and he's very comfortable playing with a lead. 14 under round here I'll take that every year and take my chances.' World No 1 Rory McIlroy, who needed to win to complete a career grand slam, finished fourth after a closing 66 and added: 'Jordan started fantastically well and has kept his foot down and been really impressive.' Tributes poured in for Spieth from his fellow players and other stars as the world reacted to the young Texan's impressive display.
Jordan Spieth wins 2015 US Masters after finishing 18-under at Augusta . Spieth became the first man ever to reach 19 under par in the Masters . Justin Rose and Phil Mickelson (both 14 under) finished joint second . READ: Spieth has world at his feet after record-breaking Masters triumph . Spieth: Winning the Masters has been the most incredible week of my life .