Harrison has been signed on a three and a half year contract by the Citizens but will spend the rest of the 2017-18 campaign on loan to the English Championship club.
Terms of the transfer were not released but sources tell Goal that NYCFC will receive a $6 million transfer fee in a deal that also includes performance bonuses and a sizable sell-on clause.
Stoke City had been interested in Harrison's services as well, but saw repeated bids rejected, including its most recent one in the neighborhood of $7 million dollars.
“I can’t wait to get started over here,” Harrison said in a statement published on Manchester City's official website.
“I’ve really enjoyed my time with New York City and I’d like to thank Patrick Vieira and his coaching staff for helping me to develop as a player.
The Stoke-born Harrison returns to England, where he was born and raised before moving to the United States to attend high school. He spent time in Manchester United's youth academy before his move to the United States as a teenager. Harrison spent a year starring for the Wake Forest University soccer team before turning professional in MLS.
Harrison was the No.1 selection in the 2016 MLS SuperDraft, taken by the Chicago Fire but acquired in a draft-day trade by NYCFC. The 21-year-old midfielder played two seasons in MLS and experienced a breakout campaign in 2017, scoring 10 goals and adding six assists for NYCFC.
The winger's performances earned him a call to the England under-21 squad this past summer, and also attracted the attention of Middlesbrough manager Tony Pulis as he looks to strengthen his side for a promotion push back to the Premier League. Middlesbrough is currently eighth in the Championship table, four points off sixth place and the last spot in the promotion playoffs.
This is the second move in the week which involved a NYCFC player moving to Manchester City. Over the weekend Umbro announced Mix Diskerud had signed with the Premier League giants. Diskerud is not expected to feature or train with the Manchester City first team, and is expected to be sold this summer. That move allowed NYCFC to remove Diskerud's contract — a guaranteed deal — from its salary cap in 2018, while effectively transferring the loss to Manchester City's books.
MLS has not made any significant changes to its guidelines regarding interactions between MLS teams and sister clubs (Manchester City-NYCFC, New York Red Bulls-RB Leipzig-RB Salzburg, Montreal Impact-Bologna), though there has been a clear increase in activity within those partnerships.