Merson believes former PSG boss Emery has started a revival at the Emirates, but fears Arsenal's backline will let them down.
Laurent Koscielny, Dinos Mavropanos, Mohamed Elneny and Hector Bellerin were all ruled out, while Sead Kolasinac and Nacho Monreal needed fitness tests-and neither eventually made the match-day squad.
The big Premier League teams left in the Carabao Cup, will play their fourth round fixtures on Wednesday.
At the beginning of the season, the Football Association announced that yellow cards received will no longer be carried across varying football competitions, staying specific to each competition the booking is awarded in. Nacho Monreal, Sead Kolasinac and Konstantinos Mavropanos all remain out.
Real have won the Champions League there seasons in a row and four out of the last five years.
Federer reaches 14th Swiss Indoors final by beating Medvedev
Federer clinched minutes after saving a break point, taking his first match-point chance when Copil sent a backhand into the net. But a run of five consecutive games for Federer maintained the world number three's spectacular run in this competition.
However, Salah struggled to break into the team at Stamford Bridge, and spent time in Italy with Fiorentina and Roma before finally arriving at Anfield last summer.
However, he seemed to rule out going to another Premier League club.
The Leeds loanee had earlier hit the bar but his evening ended prematurely when he was sent off for fouling substitute Pierre-Emerick Aubameyang as Arsenal secured a 2-1 win and a quarter-final clash at home to local rivals Tottenham.
After a hard start to the season, Cech suffered a hamstring injury in the win over Watford last month and was only named on the bench following his return to fitness in the 2-2 draw with Crystal Palace in Arsenal's last game on Sunday.