Jason Puncheon scored the only goal of the game midway through the first half of his Millwall debut to secure the points and leave Jackett in high spirits.
Jackett said: "I felt we started the game very well. We were very direct and set a fast pace and I think that maybe surprised Middlesbrough a bit.
"Our fans were very noisy right from the start too and I think that made a contribution in setting the tone of the game."
Source: PA
Source: PA