(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 don'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.  QUESTIONS:

Q1:
1. What sport is being played?
2. Which sport appears in the article?
3. What is the sport at the US Open?
Q2:
1. What event was tennis being played at?
2. What was the tennis event?
3. Which tennis championship does the article discuss?
Q3:
1. What was the location of the US Open?
2. Where was the US Open played?
3. What city did the US Open take place in?
Q4:
1. What player has won five times?
2. What five time winner appears in the article?
3. Who is the five time champion that the article discusses?
Q5:
1. Who loses to Roger Federer?
2. Who does Roger Federer defeat?
3. Who is bested by Roger Federer?
Q6:
1. What did Roger Federer say about playing conditions?
2. What was Roger Federer's description of playing conditions?
3. How did Roger Federer talk about the playing conditions?
Q7:
1. What did Roger Federer say about his playing?
2. What was Roger Federer's description of his playing?
3. How did Roger Federer say that he played?
Q8:
1. What is the name of the home favorite?
2. Which player is the home favorite?
3. What player is favored on his home turf?
Q9:
1. What is the American's name?
2. Which player is American?
3. What player is from the United States?
Q10:
1. How old is Ryan Harrison?
2. What is Ryan Harrison's age?
3. How old is the American player?
Q11:
1. Did Ryan Harrison beat his opponent?
2. Did Ryan Harrison win?
3. Did Ryan Harrison come out on top?
