Doncaster Rovers made their dominance pay to extend their unbeaten away record to six games.
Rovers enjoyed much the better of the first period at Roots Hall and led 1-0 at the interval against Southend United. However, despite commanding matters the breakthrough did not arrive until the 44th minute.
Recalled Nathan Tyson went on a surging run before crossing low for Andy Williams, who rifled in an effort from the tightest of angles. It was in-form Williams’s 13th goal of the season, and his 10th in 12 matches.
Earlier the Shrimpers’ goalkeeper Dan Bentley was twice tested by Craig Alcock and then captain James Coppinger as the visitors made an excellent start to the game.
Andy Butler headed narrowly over the top, and at the other end Thorsten Stuckmann had to be at his agile best to keep out Jack Payne’s deflected strike.
Rovers went agonisingly close to doubling their lead just two minutes after the restart.
Paul Keegan did well to find space on the edge of the Southend box before drilling in a superb shot that struck the outside of a post.
The deserved second goal came in the 55th minute, Aaron Taylor-Sinclair volleying in off the underside of the crossbar as he dived in to meet Grant’s precise corner-kick.
Three minutes later it was 3-0. Williams was bundled over by Adam Thompson and Tyson coolly beat Bentley to register his fifth goal of the season.
Southend United: Bentley, White, Thompson, Barrett, Coker, Leonard, Rea (Deegan 53), Atkinson (Worrall 41), Payne, Hunt, Mooney (Pigott 70). Unused substitutes: Prosser, Ted Smith, McLaughlin, O’Neill.
Doncaster Rovers: Stuckmann, McCullough, Alcock, Butler,Taylor-Sinclair, Evina (Lund 81), Coppinger (Middleton 82), Keegan, Grant, Tyson, Williams. Unused substitutes: Chaplow, MacKenzie, Jack McKay, Mandeville, Marosi.
Referee: Lee Collins (Surrey).