For the second week in a row, Arsenal blew a 2-0 lead. This makes Manchester City the clear favorite to win their fifth Premier League title in six years.
Injury-hit Tottenham and Newcastle both lost, and the bottom three teams all lost, which could be a big boost for Manchester United's chances of getting into the top four.
After Arsenal's bad 2-2 draw at West Ham, Mikel Arteta and Bukayo Saka walked down the tunnel with their heads in their hands.
The Gunners, who were up 2-0 at the London Stadium, lost points they couldn't afford to lose in their race for the title against a Manchester City team that was playing well.
Still four points ahead of second-placed City, who have a game in hand, Arsenal's young team is starting to look like it's feeling the pressure of the title race.
Pep Guardiola's team has won 10 straight games in all competitions. In recent years, they have dominated the Premier League and know what it takes to win the title.
Because of what happened on Sunday, Arsenal may have to beat City at the Etihad on April 26, which could be hard for them to do.
"We're playing with a lot more freedom, more energy, and so much more positivity, which is a huge credit to the gaffer for coming in and helping us with that."