Forest have had a decent start to life with the Frenchman, currently sitting sixth in the Championship after eight matches, having only lost one.
The Gunners are expected to make plenty of changes, but will have to be on their guard against their second-tier opponents.
Arsenal go into this match on a high after returning to winning ways in the Premier League against Aston Villa on Sunday.
Unai Emery will have breathed a huge sigh of relief when he returned to the dressing room, with his team having scored twice late on to seal a 3-2 victory over the Villans.
Ainsley Maitland-Niles's red card just before half time, with Arsenal already trailing, had complicated matters, but the Gunners managed to just about get over the line.
It has been a mixed start to the season in the league for Arsenal - with that Villa victory being their first since defeating Burnley on August 17.
The Europa League provided a welcome boost last Thursday, however, when they defeated Eintracht Frankfurt 3-0 in Germany. Emery will be hoping Wednesday night's EFL Cup clash with Nottingham Forest can have the same effect.
Forest go into the match having only lost one of their opening matches in the Championship under Frenchman Lamouchi.
The 47-year-old has brought back a feel-good factor for Forest, who go into this match with nothing to lose.
Lamouchi has made Forest solid at the back and they have conceded only one goal in their last four matches, so what is likely to be a young Arsenal team may have to patient if they are to find their way through.
Arsenal form: WLDDWW
Nottingham Forest form: DWWDWW
Unai Emery will once again be unable to select Alexandre Lacazette as the Frenchman recovers from an ankle issue.
The 28-year-old hitman hasn't featured since scoring in the Gunners' 2-2 draw with Tottenham.
There could, however, be a return for long-term absentee Hector Bellerin. The Spaniard ruptured his Achilles tendon back in January, but came through unscathed for Arsenal's Under-23 side on Friday night.
Another man that featured for the young Gunners that night was new £25m signing Kieran Tierney, who could be in line for an Arsenal debut.
Konstantinos Mavropanos remains injured and unavailable, and Ainsley Maitland-Niles misses out with suspension after Sunday's red card.
Lamouchi also has injury concerns, with Wolverhampton Wanderers loanee Rafa Mir among those sidelined.
The forward would have likely been in line to feature in this match having started both EFL Cup games so far, but his absence could see Lewis Grabban retain his place, particularly with Sammy Ameobi also a doubt.
Arsenal possible starting lineup:
Martinez; Bellerin, Chambers, Luiz, Tierney; Willock, Xhaka, Torreira; Ozil, Aubameyang, Nelson
Nottingham Forest possible starting lineup:
Samba; Cash, Dawson, Worrall, Ribeiro; Watson, Sow; Lolley, Silva, Carvalho; Grabban
We say: Arsenal 0-1 Nottingham Forest
The Gunners have been unpredictable of late and, if Emery is to make a slew of changes, Lamouchi's Forest could give them a shock. The visitors are expected to field a strong lineup and that could be enough for them to produce a memorable upset.
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