Despite nursing a slight hamstring injury that saw him substituted, the 22-year-old set up two Blues goals and scored their third.
Southend took the lead on eight minutes when Nicky Bailey brought the ball from his own half and swapped passes with debutant Leon Clarke before rifling a left-foot shot past former Shrimpers keeper Simon Royce from 14 yards.
The Blues could have doubled their advantage after 24 minutes when Matt Harrold's flicked header found Leon Clarke - on a three-month loan from Sheffield Wednesday - whose overhead kick was palmed over the bar for a corner by Royce.
But the hosts got a second goal a minute before half-time, with Leon Clarke again at the heart of things.
His lay-off released Alan McCormack and he pulled the trigger just inside the box to beat Royce.
Gillingham struggled to threaten Steve Collis' goal, with Gary Mulligan firing over the bar and former Southend midfielder Mark Bentley shooting wide.
The Kent side's best chance came at the end of the half when a long Steve Lomas throw from the left was headed goalwards by skipper Ian Cox at the far post but his effort was caught by Collis.
Assistant referee Matt Stewart took over the whistle for the second half after referee Grant Hegley pulled a hamstring.
Leon Clarke put Blues 3-0 up after 59 minutes after doing a one-two with McCormack and then delaying his shot before cheakily chipping an advancing Royce.
Harrold then wasted a good chance by shooting straight at Royce before Gills substitute David Graham shot over and Delroy Facey headed over the bar.
Southend skipper Kevin Maher hit Royce's left post and then the keeper came out to smother Harrold's effort from close range before substitute Mark Gower hit the crossbar.