"He can take players on and he likes to cut in a lot and I like to make late runs into the box," said man of the match McKennie of Pulisic.
"So we always tell each other whenever he cuts in, look for me at the back post or look for me inside the box, because I am going to run.
"It’s a connection that we are developing and improving on and hopefully in the next games it will be even better."
Ranked 79th in the world, 49 places behind the United States, Curacao were not overawed by their opponents and U.S. goalkeeper Zack Steffen had to be on his toes to deny Gevaro Nepumoceno on more than one occasion.
At the other end, Eloy Room made several stops for Curacao and captain Cuco Martina thought his team had done themselves proud.
"We fought like lions," he said. "We did everything to win. The chances that we got, we didn't score."
The win for the United States sets up a semi-final against Jamaica, runners-up at the last two Gold Cups, in Nashville on Wednesday.
Mexico will play Haiti in the other semi in Glendale, Arizona the day before.
The final will be held in Chicago on July 7.
(Reporting by Andrew Downie; Editing by Peter Rutherford)
