"Long time since I've been here," the former Beatle told the crowd, then paused to take it all in.
Citi Field is the successor to Shea Stadium, where the Beatles played a historic concert in 1965 that's regarded as the precursor to the stadium rock concert.
Patty Parker attended Friday night's show and remembers the 1965 show well.
"I was three rows from the top. I was 10 years old," she said. "He captured that same tune; I'm so blown away."
Several times on Friday, McCartney alluded to that magical night 44 years ago. But he was also made it clear that it was less than perfect at times, saying: "The first time we played here, we couldn't hear a thing because of all the girls screaming and the stadium sound system."
Friday's two-and-a-half-hour show went more smoothly, highlighted by fireworks on and off the stage for "Live and Let Die" near the show's end.
McCartney played more than 30 songs, covering the Beatles, Wings and his solo catalog. When he introduced "I'm Down," he said it was also played at the Shea Stadium concert.
The crowd rocked most of the night, which was also filled with heartfelt dedications. The most poignant went to McCartney's late wife before an emotional version of "My Love."
"We'd like to do a song dedicated to Linda," McCartney said. "She was a New York girl."
