The Red Devils’ legendary former boss was pictured in the Old Trafford directors’ boss prior to kick-off.
Photographers had earlier snapped him arriving at the stadium looking smart in a navy blue suit while speaking on his mobile phone.
United are heading in the right direction under new manager Jose Mourinho after three years in the relative wilderness since Fergie’s retirement in 2013.
They started the season slowly but had won five games on the bounce in all competitions going into the Boro match.
Mourinho recently revealed Ferguson has been back to United’s Carrington training ground on several occasions this season after three years away.
“He had not been back since he left, but I brought him back to be with his people,” Mourinho told the United We Stand fanzine.
“I wanted the players to see the big man and for me and him to share some minutes and have lunch together. I enjoyed it, he enjoyed it.
“I’m the type of person who does not see ghosts. I respect the past and I know he loves the club.
“We have good relations and I know this is his house.
“When he wants to come here, to the dressing room, to see the players train, he knows he is more than welcome.”