Johnson is the No. 8 player in the country and top offensive tackle.
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Henry is the 15th player to commit to Ohio State for 2019 and the sixth from Ohio, one more than signed with the Buckeyes either of the last two years.
He is also the fourth player from the Cincinnati area to commit to Ohio State in this class, matching the most since 1990.
Cody Simon, a four-star linebacker from St. Peter's Prep in Jersey City, N.J., also committed Saturday.
Ohio State entered the weekend with the No. 8 class in the country and No. 2 in the Big Ten.
The Buckeyes were on top of the conference until a run of recruits picked up by Michigan in the past week, lifting Jim Harbaugh’s 2020 class to No. 5 in the country.
Adding Simon and Henry pushed them back in front of the Wolverines and up to No. 5 nationally trailing Clemson, Alabama, LSU and Georgia.