On target: Arsenal striker Danny Welbeck celebrates his goal
Fedor Chalov and Kirill Nababkin scored for CSKA to set Arsenal nerves jangling in the Russian capital, as the hosts looked to overturn a 4-1 deficit from the first leg.
But Danny Welbeck pulled one back before Aaron Ramsey levelled the scores on the night in stoppage time, taking the Premier League side through 6-3 on aggregate.
It was another night of comebacks in a crazy midweek in Europe, with Marseille and Red Bull Salzburg producing stirring performances to overturn first-leg deficits and go through.
Salzburg lost 4-2 to Lazio in Rome last week but won 4-1 in the return in Austria, despite Ciro Immobile giving the Italians a second-half lead on the night.
The hosts proceeded to score four times in 20 minutes to advance 6-5 on aggregate.
Marseille recovered from losing 1-0 away to RB Leipzig last week, and from falling behind to the Germans inside two minutes in the return at the Velodrome, as they won 5-2 on the night to progress 5-3 on aggregate.
A brilliant Dimitri Payet finish for Marseille’s fourth was a highlight as they made it through to a first European semi-final since 2004.
Atletico Madrid are also through, and remain the favourites to win the trophy in Lyon next month — they were beaten 1-0 on the night away to Sporting Lisbon but progressed 2-1 on aggregate.
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