Derby County fell to a 3-0 defeat to Charlton Athletic at The Valley in their return to action after the international break.
The Rams entered the fortnight break on a high after going unbeaten in the five games that sandwiched the first two international breaks, but they weren’t able to regain that form against the South London team.
Early goals in both halves from Macauley Bonn then Naby Sarr put the Addicks on the front foot before Conor Gallagher sealed the victory with a fine strike from distance.
The home side took the lead after just six minutes when Jonny Williams broke down the left and crossed into the area for Bonne to sweep into the bottom corner.
Although the Rams held the bigger share of possession in the half, the Addicks kept them at bay on the attack. While down the other end, Bonne and Williams looked to combine again to come close to doubling the lead on the 20-minute mark.
This time, Bonne whipped a low cross in from the right, but it skimmed past Williams and glanced past the far post. Just two minutes later, Roos made a fine save to deny Bonne.
The forward struck from just inside the area and the Rams stopper dived to palm the effort over the top right corner.
Derby’s only shot of the half fell to former Charlton loan player, Krystian Bielik. After good build-up play around the area, the ball fell to the midfielder from 25-yards out, but his effort was a comfortable save for Dillon Phillips.
Charlton got the second-half underway as they did the first, with a goal just three minutes coming after the restart. Josh Cullen sent a corner towards the back post for the defender Sarr to turn in.
The Addick made it three with a brilliant strike by Gallagher that Roos could do nothing to stop. He shifted to his dominant foot before rifling his effort from range into the top of the net.
In the dying minutes, Phillips made back-to-back saves to deny Derby of a consolation goal. First, he punched away a long-range effort by Tom Lawrence when he whipped in a goal-bound shot from the left.
Mason Bennett then burst into the area to go one-on-one with the keeper who closed the forward down to block his shot.
The Rams return to Pride Park Stadium on Wednesday evening to take on Wigan Athletic, looking for their third Consecutive home victory.
Charlton: Phillips; Solly, Lockyer, Pratley, Sarr; Forster-Caskey, Gallagher (Kayal, 78); Leko, Cullen, Williams (Field, 32); Bonn (Hemed, 74)
Unused Subs: Amos, Oshilaja, Pearce, Oztumer
Derby County: Roos; Bogle, Davies (C), Clarke, Malone; Shinnie, Bielik (Holmes, 60); Waghorn (Jozefzoon, 60), Paterson (Bennett, 76), Lawrence; Martin
Unused Subs: Hamer, Wisdom, Dowell, Lowe