Torres found the net from close range after a low cross by Luciano Vietto in second-half injury time, scoring his first goal since September. Fans at Vicente Calderon Stadium gave the striker a standing ovation, and loudly chanted his name after the final whistle.
"Finally," Torres said. "After many games and many years, this is something that will stay with me forever. I know I'll be among the club's greatest goalscorers. It's a prize for me. When I was a kid and came to the Calderon, the most that I dreamt of was to wear this jersey someday, once."
The victory halted Atletico's four-game winless streak, and moved the club closer to leader Barcelona.
Atletico was tied with Barcelona on points, but the Catalan club has two games in hand. Barcelona visits Levante on Sunday with a chance to match its all-time record of 28 games without a loss. Third-place Real Madrid, which plays at Granada on Sunday, is four points behind the leaders.
Villarreal, which couldn't manage more than a 0-0 draw with Athletic in Bilbao, remained fourth.
Atletico controlled possession but wasn't able to create many significant scoring chances.
Eibar opened the scoring after Niguez's mistake moments into the second half. He tripped on the ball while trying to control it and gave possession to Sergi Enrich, who set up Keko's easy goal from just outside the area.
Atletico rallied with headers by Gimenez and Niguez himself. Torres came off the bench to seal the win with his goal just before the end of the match. Torres' last goal was in the league's fourth round, again against Eibar. It was his third league goal this season after missing several matches recently because of injury.
"I'm very satisfied, we went through a difficult situation early in the second half and the team reacted with a lot of personality," said Atletico coach Diego Simeone, who earned his 100th league win.
Atletico was coming off losses against Barcelona in the Spanish league and Celta Vigo in the quarterfinals of the Copa del Rey, a result that eliminated the team from the competition.
Atletico rebounded even though Simeone couldn't count on three key defensive players: Diego Godin and Filipe Luis were suspended because of red cards received against Barcelona, while Juanfran was out because of an accumulation of yellow cards. In addition, midfielder Augusto Fernandez was injured and striker Jackson Martinez just transferred to Chinese football.
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