Mikel put up a commanding performance on his fifth Championship appearance as goals from Jonathan Howson and Ashley Fletcher sealed victory for the hosts at the Riverside Stadium.
The 31-year-old has been a key player for Middlesbrough since his arrival and has won the hearts of the club faithful who composed a song for him.
McClaren, an ex-Boro gaffer, has also hailed the signing of the Nigeria international who returned to England as a free agent in January and highlighted his impact in Tony Pulis' side who are presently fifth in the Championship table.
"I think Mikel has been an excellent signing," McClaren told Teesside Live.
"You always have that one player who gives you stability, control, never gives the ball away.
"They've got one of the best, a Champions League winner. He dominates in there, he takes care of the ball.
"Every team needs a Mikel. He's certainly the kind of enforcer in there, defensively and he keeps the ball ticking.
"I've been impressed with him. He's given another edge to Middlesbrough."
Middlesbrough have lost just a game the former Chelsea midfielder has featured in, winning three and settling for a draw in his five league outings.
The Riverside Stadium outfit will continue their push for an automatic promotion spot with a visit to Wigan Athletic on March 2.