In the 19th minute, United drew level with an opportunist finish from Crawford. Kyle Asante's speculative 30-yard drive should not have posed too many problems for goalkeeper Danny Sambridge but the custodian could not hold the long-range effort and Crawford was on hand to whip the rebound into the roof of the net.
Seconds later Crawford, playing largely in a more withdrawn role off of two forwards, flicked the ball into the path of the Milner, whose shot lacked purchase and was claimed by Sambridge.
However, just after the half-hour mark, Blues took the lead with an immaculately-worked goal. Ferdinand's simple pass found Owinja, who quickly tapped into the path of Merrick James-Lewis. He moved the ball on to Asante, bursting down the inside-right channel, and the forward squeezed his tenth youth team goal of the season inside the left-hand upright from an acute angle.
Southend were by now looking much more comfortable on the ball, with boss Duncan later singling out Ferdinand for particular praise in midfield, and further opportunities arose in the latter stages of the half as James-Lewis flashed over, Sambridge tipped a Jamie Dennis corner onto his own woodwork and Owinja crashed a 35-yard shot against the bar.
Within three minutes of the restart after half-time, Blues had made it 3-1. Crawford's persistence on the right earned a corner, which Dennis delivered to Asante at the near post. He controlled the ball and attempted to slide it into the six-yard box, but a Daggers defender intercepted it and inadvertently tapped it into his own goal.
Crawford then snapped at a shot, firing Asante's square pass over from close range before Owinja made an excellent challenge inside his own area to stop a Dagenham forward from getting a shot in on the Southend goal.
The visitors appeared content with their lead and, although Daggers continued to press hard in midfield, they struggled to craft any further openings. November Player of the Month Dennis almost created a late chance for Blues when he burst down the left, but his cut-back just eluded Crawford.
A good training ground set-piece routine saw Reynolds slide the ball down the left wing for Nesbitt, who hung a cross up to the back post. Unfortunately, Crawford could not quite direct his header on target as he stretched his neck skywards with two minutes remaining.
There was a sting in the conclusion as Dagenham pulled a goal back two minutes into stoppage time when a substitute bravely went in for a header as Bentley attempted to claim a cross and managed to bundle the ball over the line, but there was no time for a concerted push for an equaliser and Southend instead find themselves well clear at the top as they enter their Christmas break.
Southend United: Daniel Bentley; John Owinja (Adetayo Osifuwa 59), Callum Whittaker, Duran Reynolds, Teddy Nesbitt; Kane Ferdinand; Merrick James-Lewis, Jamie Dennis (Alex Woodyard); Harry Crawford; Kyle Asante (Julian Okai 85), Marcus Milner.
Substitutes not used: George Smith, Akim Abiola-Daramola.
Goals: Crawford (19), Asante (31), own goal (48).
Cautioned: Reynolds (54 - dissent), Ferdinand (78 - dissent).
Thanks to the Shrimpers Trust website for the reprinting of these reports, for the Trust's own youth section, go here:
www.shrimperstrust.co.uk/home.asp?page_id=10