Leyton Orient extended their lead at the top of Sky Bet League Two to seven points as a Paul Smyth stunner and Alastair Smith own goal secured a 2-0 win at home to Sutton.
Smyth opened the scoring after 61 minutes when he collected a pass from Theo Archibald and lashed the ball into the top-right corner from 20 yards for his ninth goal of the season.
The outcome was settled by an own goal in the 79th minute. A Tom James throw-in from the right was helped on by Omar Beckles and Smith deflected the ball into his own net.
Sutton created little throughout the match to unsettle a tight Orient defence.
A scrappy first half provided few chances, although Archibald, who was a constant threat, almost broke the deadlock just after the half-hour.
Charlie Kelman was felled on the edge of the area and Archibald beat the wall and goalkeeper with his free-kick but saw the ball crash against the underside of the crossbar before being scrambled to safety.