Olsson’s fine first-time hit from Tom Ince’s pass ensures Derby will stay fifth in the Championship whatever the results of Saturday’s other matches, while Forest could be just seven points above the relegation zone if Rotherham, MK Dons and Fulham all win.
Forest’s high-tempo, high-pressing game worked perfectly in the opening 25 minutes, forcing error after error from the Rams, which in turn got the home crowd agitated and restless.
Redknapp trudged from his seat in the stands towards the dressing room at the break, and whatever he and head coach Darren Wassall said worked a treat.
Derby could barely put a foot right in the opening 45 minutes, but started to win the midfield battle and looked the more threatening of the two sides after half-time.
Too much at stake
The inescapable truth is of a derby match offering plenty of blood and thunder and very little in the way of quality or goalmouth incident. If bone-crunching challenges, blocked shots, misplaced passes and numerous free-kicks is your thing, then it was ideal.
Sadly, there was precious little else to talk about.
Ince looked lively for the hosts, with a couple of surging runs that came to nothing, while a fierce low strike that went straight at Reds goalkeeper De Vries early in the second half was the first effort on target.
Forest had looked comfortable but, aside from a couple of long-range efforts, they were also poor in the final third and they had no way back into things after Olsson’s moment of quality.