This is one outlet's own report from Yahoo Sports — the article as it was filed.
Sooners' Cole Sullivan brings 'great versatility' to Norman

The Oklahoma Sooners added several pieces in the transfer portal in hopes of taking the team to the next level after a College Football Playoff berth in 2025. Oklahoma added 16 players in the portal this cycle.
One of the biggest wins was former Michigan Wolverines linebacker, Cole Sullivan. He had 44 tackles, five tackles for loss and two sacks last season. He also intercepted three passes. He elected to enter the portal after head coach Sherrone Moore was let go and eventually replaced by Kyle Whittingham. Sullivan chose the Sooners over a return to Ann Arbor.
