Forest Green lost top spot in the National League as Southend twice hit back to earn a 2-2 draw.
Rovers, who were looking for an eighth successive win, slipped behind York on goal difference after their 4-0 win over Yeovil.
Tom Knowles threatened for Forest Green after 16 minutes but his effort was well saved by Collin Andeng-Ndi, with the goalkeeper also on hand to deny Harvey Bunker after 29 minutes.
Southend came close when James Morton headed wide from a 38th-minute corner, but moments later the leaders were ahead when Bunker met Jamie Robson’s cross to score for the third successive match.
The hosts levelled after 63 minutes when Nathan Ralph converted from close range after a long throw.
Rovers regained the lead after 73 minutes as Christian Doidge thrashed in when Andeng-Ndi spilled Teddy Jenks’ cross, but Oli Coker equalised again four minutes later by smashing home a loose ball inside the box.
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