Manchester City's Premier League title hopes were dealt a crushing blow when they were held to a 2-2 draw by bottom club Sunderland at the Etihad Stadium on Wednesday.
Everton suffered a shock 3-2 home defeat by mid-table Crystal Palace at Goodison Park to put a huge dent in their bid for a top-four finish.
City, champions in 2012 and runners-up to neighbours Manchester United last season, failed to respond to their 3-2 defeat at leaders Liverpool on Sunday and stayed third in the table on 71 points from 33 matches, six behind Liverpool and four adrift of Chelsea with only one game in hand.
Liverpool are in pole position to claim their first English title in 24 years, but they still have to play Chelsea at Anfield on April 27.
"We did not play well but we had in our mind the game against Liverpool," City manager Manuel Pellegrini told Sky Sports.
"It is not enough because we have Liverpool and Chelsea on top of the table and we needed to add three points - will see in the future what will happen but our chances are less."
Sunderland remained rooted to the bottom of the table with 26 points from 33 matches, six points adrift of 17th-placed Norwich City.
"We deserved better," manager Gus Poyet said. "We conceded a goal after two minutes at Manchester City and every single person in the world expected us to lose from there.
"But we passed the ball and created chances. We kept believing."
After the damaging defeat by Liverpool, City knew anything other than a win would seriously dent their title hopes and a slick passing move enabled Fernandinho to fire them ahead after two minutes.
But with talismanic midfielder Yaya Toure missing through injury, City lacked a cutting edge and Sunderland striker Connor Wickham was in the right place on 73 minutes to convert Emanuele Giaccherini's left-wing cross and score his first Premier League goal since 2011.
City have won just twice in their last eight games against Sunderland and Wickham put Poyet's side in front after 83 minutes when he beat Joe Hart at his near post.
But Sunderland's hopes of a shock victory were dashed when goalkeeper Vito Mannone spilled Nasri's shot into his own net two minutes from time.
Goals from Jason Puncheon and Scott Dann gave Crystal Palace a 2-0 lead at Goodison Park before substitute Steven Naismith pulled a goal back for Everton.
Cameron Jerome's strike restored Palace's