Torres, 32, was hit from behind by Deportivo's Alex Bergantinos in a clash of heads five minutes from time and hit the ground hard as he appeared to have already lost consciousness.
"A cranial and cervical CT scan carried out on Fernando Torres has ruled out that the Rojiblanco striker has suffered any alterations or traumatic injuries," Atletico said in a statement.
"Our player, who is stable, conscious and oriented, had to be removed by ambulance after being stabilised according to the usual protocol, before entering the Model Hospital of La Coruna, where he will spend the night in observation."
Players from both sides immediately called for medical attention when Torres hit the ground.
Distressed Atletico defender Jose Maria Gimenez was seen crying, whilst Deportivo fans gave the former Spanish international a standing ovation as he was carried from the field.
"We are all scared," Atletico left-back Filipe Luis told BeIN Sports.
Photo: Miguel Riopa / AFP
"The news we have received until now is good. The most important thing is that Fernando is ok."
Atletico's Sime Vrsaljko and captain Gabi have also been praised for reacting quickly to ensure Torres didn't swallow his tongue whilst unconscious.
The visitors had to play out seven minutes of stoppage time with 10 men as they had already made all three substitutions.
Former West Bromwich Albion manager Pepe Mel was making his bow as Deportivo coach after only being hired on Wednesday.
And the hosts made the perfect start when Florin Andone capitalised on a poor goal kick from Jan Oblak to run through and slot past the Slovenian.
Atletico responded after half-time and equalised in stunning fashion 22 minutes from time when Antoine Griezmann thrashed home a shot from fully 30 yards.