Meanwhile, after their defeat at Cardiff City, the Tykes make the trip to the East Midlands sitting just three points above the relegation zone.
On the back of three draws against Nottingham Forest, Cardiff City and Bournemouth, Cocu may have felt that his Derby side were heading in the right direction.
However, Wednesday's late defeat at home to Queens Park Rangers left the Rams with just one win from 10 games this season, a return which has put the head coach on the brink of the sack.
With an international break to come, Cocu may be provided with one final opportunity to get a much-needed victory on the board, but this side have now claimed just 10 points from their last 16 outings in the second tier.
Although holding a contract until 2023 has provided Cocu with extra time to get things right at Pride Park, his players are performing well below their capabilities.
Now two points adrift of safety, losing to one of their relegation rivals would almost certainly leave the powers-that-be with no other option but to pull the plug on a project which was supposed to get the club back in the Premier League.
In the opposite dugout, Valerien Ismael will be taking charge of just his fourth game, already collecting the same points as Cocu despite only being appointed as Barnsley boss on October 23.
The Tykes were comprehensively beaten by Cardiff earlier this week, but recent triumphs over Queens Park Rangers and Watford have moved the club away from the drop zone.
At a time when they remain just seven points adrift of the playoffs, the manner of both wins will provide Ismael with optimism that his team can continue to make further progress up the standings.
Former Leicester City midfielder Matty James has already established himself as a key player at Oakwell, making four appearances for the club in quick succession despite his lack of game time in recent seasons.
Derby County Championship form: LLDDDL
Barnsley Championship form: DDDWWL
Having missed the previous three matches, Cocu must decide whether Wayne Rooney should start two games in quick succession.
Louie Sibley is standing by should the veteran drop down to the substitutes' bench, and further alterations are expected elsewhere in the side.
Ismael has hinted that Cauley Woodrow should be back in contention for Barnsley after a hamstring injury.
The Barnsley boss has also spoken highly of Victor Adeboyejo, suggesting that the forward may be in line for his first league start of the season.
Derby County possible starting lineup:
Marshall; Wisdom, Davies, Clarke, Forsyth; Bird, Shinnie; Jozwiak, Rooney, Holmes; Waghorn
Barnsley possible starting lineup:
Walton; Sollbauer, Helik, Andersen; Frieser, Mowatt, James, Styles; Chaplin, Simoes; Adeboyejo
We say: Derby County 1-2 Barnsley
While this game is effectively win or bust for Cocu, we feel that the Dutchman may still opt against throwing caution to the wind. That would only play into the favour of the visitors, who will relish the opportunity to heap further misery on the Rams.