Sports Browns COVID-19 outbreak: Case Keenum tests positive, team turns to third-string QB Nick Mullens December 16, 2021 Nate Ulrich, Akron Beacon Journal Comments Off on Browns COVID-19 outbreak: Case Keenum tests positive, team turns to third-string QB Nick Mullens Backup quarterback Case Keenum and safety Ronnie Harrison are among the Browns players who tested positive for COVID-19 on Thursday.