The Gunners came from a goal down to book their place in the final of the cup competition and they will take on Manchester City in the showpiece next month.
Monreal earned plenty of praise for his determined performance for the north London side as he helped Arsene Wenger’s men to claim the victory.
The defender was involved in Antonio Rudiger’s own-goal after Eden Hazard had put Chelsea ahead in the seventh minute, before Granit Xhaka ended up scoring the winning goal on the hour-mark.
Monreal has been in top form for the Gunners in recent weeks and Henry was full of praise for the defender following his strong display in Arsenal’s victory over Chelsea.
Speaking to Sky Sports after the game, Henry said: “Nacho Monreal [was the key man].
“For his position, as a left-back, the way he was driving the team forward with his commitment and the number of interceptions he had…
“It’s contagious when you see a guy on the field fighting for every ball, diving for everything, trying to push everybody forwards.
“We were expecting [it from] others but he came up with it. I thought he was absolutely brilliant.”
Arsenal now have the weekend off before turning their attentions towards their Premier League clash against Swansea City at the Liberty Stadium on Tuesday night.
The north London side are currently in sixth place in the Premier League table as they look to try and break back into the top four this season.
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