Boro won at Forest for the first time since 1999, thanks to goals from David Nugent and Daniel Ayala.
Aitor Karanka’s side took the lead at the City Ground after just three minutes, but Matt Mills volleyed home from a corner just minutes later for the Reds.
Middlesbrough went ahead just past the half-hour mark thanks to a header from Ayala, and it finished 2-1 to the home team.
Following the match, midfielder Clayton took to Twitter to revel in the triumph, with goalkeeper Dimitrios Konstantopoulos, who saved a penalty from Henri Lansbury, also expressing his joy on the social networking site.
Great 3 points today . Did enough in the end thanks to our big Greek legend in the sticks @Dimster23 just hope Stuart Lancaster was there— Adam Clayton (@Clayts15) September 19, 2015
Red aaaaaarmy!— Dimi Konstantopoulos (@Dimster23) September 19, 2015
Over the course of the 90 minutes at the City Ground, visitors Middlesbrough had 51% of the possession, took 11 shots of which nine were on target, and earned one corner.