Steve McClaren's Derby fell to a disappointing 2-0 defeat at second-placed Burnley last weekend, and their task of catching Sean Dyche's men in the Championship table became even more difficult on Saturday.
The deadlock was broken shortly after the hour mark, Steve Morison heading home superbly from Lee Martin's cross.
Forest's hopes of climbing into second appear increasingly slim following a 1-0 defeat to struggling Barnsley at Oakwell.
The result represented the perfect tonic for the South Yorkshire outfit, who had lost 5-0 at Huddersfield Town in their last Championship fixture.
With an 11-point gap to Burnley, Forest will look to firm up their play-off spot, with seventh-placed Wigan Athletic just three points behind Billy Davies' men with two games in hand.
Dougie Freedman's men were only 1-0 ahead at the break after Joe Mason notched on the stroke of half-time.
But a brace from Danny Graham - who was able to celebrate his first Middlesbrough goals for more than nine years after rejoining the club on loan in January - handed Aitor Karanka's men a 2-0 win.
On-loan West Ham midfielder Ravel Morrison scored in each half, as QPR's five-match winless run came to an end.
Sheffield Wednesday finished with 10 men as Sam Hutchinson was sent off in a 2-0 defeat at relegation-threatened Yeovil Town, while fellow strugglers Doncaster Rovers were 2-0 victors over Huddersfield Town at the Keepmoat Stadium, with Billy Sharp and David Cotterill bagging for Paul Dickov's charges.
