( CNN ) -- Five-time winner Roger Federer opened his U.S. Open account Monday with a straight sets win over Santiago Giraldo in New York . Despite surrendering his serve three times , the 30-year-old Swiss enjoyed a relatively comfortable match against the Colombian , ranked 54 in the world , winning 6-4 6-3 6-2 on the Arthur Ashe Stadium court . Leading 5-1 in the opening set , a number of uncharacteristic errors from Federer saw him squander a double-break advantage before he finally rallied to win 6-4 . The second and third sets were more straight-forward , though the world number three will be concerned about his winners-to-unforced errors ratio -- he finished with 36 winners and 35 unforced errors . `` It was quite up and down , getting used to the conditions , '' admitted Federer , in quotes carried by usopen.org . `` I do n't think I 've ever played my best in the first round but it 's important to come through them and come up with a good feeling . '' Home favorite Mardy Fish was ruthlessly efficient as he easily dispatched Germany 's Tobias Kamke 6-2 6-2 6-1 . However fellow American Ryan Harrison was not so fortunate . The 19-year old lost out to big-serving Croat Marin Cilic , 6-2 , 7-5 , 7-6 ( 8/6 ) . Seventh seed Gael Monfils ruined the U.S. Open debut of Grigor Dimitrov of Bulgaria with a battling 7-6 , 6-3 , 6-4 victory , while Czech Tomas Berdych , the number nine seed , beat French qualifier Romain Jouan 6-2 , 7-6 ( 7/4 ) , 6-1 . Elsewhere , French 13th seed Richard Gasquet trounced Ukrainian Sergiy Stakhovsky 6-4 6-4 6-0 , Serbian Janko Tipsarevic ousted France 's Augustin Gensse 6-2 7-5 6-0 , while Czech Radek Stepanek beat Germany 's Philipp Kohlschreiber 6-4 6-1 6-3 . Fifteenth seed Viktor Troicki became the first seed to fall at this year 's tournament when he was beaten in five sets 3-6 6-3 4-6 7-5 7-5 by Alejandro Falla of Colombia .
Roger Federer beats Santiago Giraldo 6-4 6-3 6-2 in first round of U.S. Open . The 30-year old Swiss finishes with 36 winners and 35 unforced errors . Other noted winners include Mardy Fish , Marin Cilic , Gael Monfils and Richard Gasquet .