Wanstead drew 18-18 with Upminster on Saturday, a result which confirms the highest they can now finish is fifth.
Upminster got off to a strong start, with young fly-half Laurence Heywood converting an early penalty.
Wanstead hit back with a penalty and an unconverted try of their own to lead 8-3.
Another Wanstead try put the hosts ahead before Will Larbey used his pace to score in the corner and cut Wanstead's lead to 13-8 at half time.
Upminster levelled soon after the break, flanker David Portch forcing the ball over the line from close range.
Replacement prop Sean Davis then turned the game in Upminster's favour with an unconverted try.
With Upminster number eight Daniel Curden in the sin bin, Wanstead pressed for an equalising try and eventually got one in the dying minutes to earn two points.