The Baggies maintained their spot at the summit of the Championship table with a draw against Millwall on Saturday, while their visitors continued to slip down the league after a promising start, as they were defeated by Birmingham City.
Match preview
Following their relegation from the Premier League last season, West Bromwich Albion appointed former Barnsley boss Valerien Ismael as manager, as they set their sights on an immediate return to the top flight.
After an opening 2-2 draw with Bournemouth, the Midlands side put their first win on the board, defeating Luton Town 3-2 before they thrashed fellow relegated outfit Sheffield United 4-0 on home turf, with Dara O'Shea, Alex Mowatt and Callum Robinson getting on the scoresheet after Jack Robinson scored an own goal to give them a lead in the first half.
Away victories over Blackburn Rovers and Peterborough United then followed, either side of a 6-0 EFL Cup defeat to Arsenal, as they headed into the recent international break with 13 points and 12 goals from the first five Championship outings.
Upon their return to action on Saturday, Ismael's men played host to Millwall, and Kyle Bartley put them ahead early in the second half, before Daniel Ballard quickly equalised to force them to settle for a point.
Having kept hold of top spot and remained unbeaten, the Baggies will now look to return to winning ways as they take on a Derby County side who continue to battle through squad issues.
After narrowly avoiding relegation on the final day of last season thanks to a 3-3 draw with Sheffield Wednesday, Derby County headed into the new campaign on the back of ongoing issues off the pitch, but they earned a commendable point on the opening day as Curtis Davies's opening goal against Huddersfield Town was cancelled out by a Naby Sarr equaliser to see the clash finish 1-1.
Wayne Rooney's side then looked set to defeat newly-promoted Peterborough 1-0 thanks to Jack Stretton's finish, but Harrison Burrows drew the Posh level in the 91st minute before Siriki Dembele hit the winner in the 10th added minute to snatch all three points for the Rams' opponents.
The East Midlands outfit managed to bounce back with a crucial 1-0 away victory over Hull City, thanks to Sam Baldock's 57th-minute effort, before earning a creditable point as they played out a goalless draw with Middlesbrough.
They headed into the international break on the back of a 1-1 draw with rivals Nottingham Forest, seeing them sit on six points from five Championship games, but their return to action produced a 2-0 defeat to Birmingham City on Friday night.
Scott Hogan punished a defensive mistake to fire the Blues ahead in the first half, before Jeremie Bela put the game out of sight with a goal in the 81st minute, condemning Rooney's men to their second league defeat of the campaign.
With the ultimate aim of avoiding the drop this season, the Rams will be desperate to pick up a result when they travel to take on the league leaders, but Rooney will know that his side faces a particularly difficult test.
West Bromwich Albion Championship form:
West Bromwich Albion form (all competitions):
Derby County Championship form:
Derby County form (all competitions):
Team News
West Brom are without centre-backs Matt Clarke and Dara O'Shea through injuries, and, while Kean Bryan was brought in to ease the defensive concerns, Cedric Kipre, Kyle Bartley and Semi Ajayi should again line up across the defence in front of Sam Johnstone.
Ismael brought Alex Mowatt, who was his captain at Barnsley last season, into the club in the summer, and the midfielder has become a crucial member of the starting XI alongside Jake Livermore.
Grady Diangana failed to impress last time out, and dangerous attacker Callum Robinson could be brought back into the starting side for Tuesday's clash, joining Matt Phillips and Karlan Grant in a front three.
Having already had their squad hit by a transfer embargo and several departing players, Derby's cause has been made even more difficult by several injuries, as forward Colin Kazim-Richards and crucial midfielder Krystian Bielik will continue spells on the sidelines, while winger Jason Knight managed to make a return to the squad last time out.
They were able to sign several free agents though, with the likes of centre-back Phil Jagielka, midfielder Ravel Morrison and forward Sam Baldock adding crucial options for Rooney.
Left-back Craig Forsyth should return to the starting XI following his suspension last time out, after 20-year-old Lee Buchanan made a costly error for the first Birmingham goal in his absence.
Knight could be handed a first start of the season after a substitute appearance last time out, while Tom Lawrence will certainly keep a spot in the attacking line.
West Bromwich Albion possible starting lineup:
Johnstone; Kipre, Bartley, Ajayi; Furlong, Livermore, Mowatt, Townsend; Robinson, Phillips, Grant
Derby County possible starting lineup:
Roos; Byrne, Davies, Jagielka, Forsyth; Shinnie, Bird; Lawrence, Morrison, Knight; Baldock
We say: West Bromwich Albion 3-0 Derby County
Given the form of the two sides so far this season, we cannot look past a convincing victory for the Baggies on Saturday.
Ismael has an abundance of attacking options at his disposal, and they should have far too much for a struggling Rams back line that has made several errors this season as Rooney looks to implement a new system.