The club announced Monday it had secured a new, year-long loan for Harrison from Manchester City for the 2020-2021 season, after it earned promotion by topping the English League Championship in 2019-2020.
Harrison was a major factor in that title-winning season, playing in all 46 league matches while scoring six goals and contributing eight assists.
The 23-year-old's showing made good on the promise he previously displayed in his first two professional seasons at NYCFC.
After entering MLS following a year playing in college, Harrison scored 10 goals in his second season in the Bronx in 2017 while appearing in all 34 MLS matches, including 33 starts.
Harrison signed with Manchester City following the season, who loaned him first to Middlesbrough and then to Leeds beginning with the 2018-2019 campaign.