Rafael and Ryan Giggs netted either side of the interval to clinch a hard-fought win that took the Reds 15 points clear at the top of the Barclays Premier League.
It was a battle, though, with the London side making life difficult for Sir Alex's men on a pitch that played havoc with United's fondness for fluid, passing football.
"We expected a tough game and we certainly got it, especailly in the first half," Carrick told MUTV. "The pitch was bouncy and bobbly and it's tight at the best of times here [at Loftus Road].
"It was just a case of adapting to the conditions and the context of the game, battling it out at times. I thought we did that well.
"Sometimes you have to do that. Throughout the season it's not always going to be pretty. Sometimes you have to grind out results, work hard and make the most of your opportunities.
"We were able to cope with QPR and, at times, we played some good football. At other times we defended well and played on the break. In the second half we controlled the game and created more chances.
"All in all I think we can be delighted with how the day's gone."
United opened the scoring on 23 minutes when Rafael ran onto a bouncing ball and sent a thunderous shot screaming into the top corner from 20 yards.
"A goal like that from Rafa put us in a great position," Carrick said. "I was right next to it. It was an unbelievable strike. It caught me by