The 40-year-old believes his side reacted well after a slow start and admits starting Juan Mata on the bench was a "difficult" decision to make
Wayne Rooney opened the scoring with a penalty after 41 minutes and found the net again shortly after halftime. Juan Mata, who started the match as a substitute, replaced Danny Welbeck after 60 minutes and struck twice to round off the win at Old Trafford.
"I did enjoy it. 4-0 it's a dream day for us and I was really pleased with the performance,” Giggs told Sky Sports.
“It's always nice to end the game like we did. Scoring goals and creating chances. And just the response of the players. First half we were a little bit slow so I just reminded them the tempo needs to be quicker and we need to be a little bit faster and they reacted well to that."
There was no place in Giggs’ matchday squad for United’s 27.5 million pound summer signing Marouane Fellaini or Adnan Januzaj, and the 40-year-old admits leaving high-profile players out of his side was a “difficult” decision to make.
"Yeah. I didn't sleep last night for that reason,” said Giggs.
“Players who weren't even on the bench, leaving the likes of Juan Mata out of the starting XI was difficult.
“It's a position I've never been put in before and it was really, really tough. Okay I'm interim manager but I'm also one of their teammates so to leave them out was tough.
“I told them all individually before the game and rightly so. A few of them were upset but they didn't sulk and you've seen the response of Juan and that's a true professional. To not moan and not sulk to come on and produce a performance like he did for half an hour."
With Louis van Gaal reportedly having agreed a deal to become United’s next permanent manager, Giggs admits he is not considering his future beyond the end of the campaign.
"It's not something I'm thinking of at the moment,” said the Welshman.
“It's just these four games, it's took so much out of me this week that I haven't really had time to look too far into the future. My next job now is getting the players ready for Sunderland."