Arsenal have a crisis on their hands after Bristol Academy handed them a third defeat in their opening four games of the Women's Super League.
Goals by Sophie Ingle and Natalia gave Academy a 2-0 win that pinned the once supreme Gunners to the bottom of the table with just one point.
Academy climbed to second, one point behind leaders Birmingham City as the league heads into a month-long break.
Notts County are third after a goalless draw at Chelsea.
Arsenal 0-2 Bristol Academy
Arsenal started brightly and only a superb Mary Earps save from striker Kelly Smith's 18-yard piledriver prevented an 11th minute opener.
But Bristol forced their way into the game and went close when Spanish striker Natalia had a 27th-minute effort that was deflected for a corner.
The visitors went in front three minutes later, Sophie Ingle turning the ball in from a cross by former Arsenal defender Corinne Yorston.
Natalia almost doubled the lead with a 57th-minute shot that hit the post.
But she got the victory clincher eight minutes later, shooting home from a cross by Spanish compatriot Laura del Rio.
And it was almost worse for the home side as Natalia fired inches wide six minutes from time.
Chelsea 0-0 Notts County
A great display by goalkeeper Christiane Endler earned Chelsea a point.
County looked the more dangerous side from the kick-off and continually stretched the home defence.
Striker Jess Clarke went close to opening the scoring with a neat turn and shot that flew just wide.
Central defender Rachel Corsie then forced Endler into an excellent save from a 20th-minute volley.
Clarke headed wide from a Sophie Walton free-kick before ex-Chelsea keeper Carly Telford had to make her first save from Drew Spence's long-range effort.
But either side of half-time Endler was again at the heart of the action following mix-ups in the Chelsea defence.
The Blues stopper pulled off the save of the match in the 67th minute, arching backwards to turn a clever Desiree Scott lob on to the crossbar.
And in the closing stages she had to make another goal-line stop from the County midfielder as Scott had an effort from 20 yards.