The Mariners never looked in any danger as they won their sixth game in a row and knocked the Ryman League leaders out of the competition.

Shaun Pearson marked his return to the starting line-up with the opening goal, before an Anthony Elding double put the result beyond doubt by half-time.

Hornchurch, who play their football two levels below the Blue Square Bet Premier Mariners, had a lively start to the second half and created a few chances to get themselves on the score sheet and take something from their long trip north.

But it was not to be for the London side and Grimsby stretched their lead further when Conor Townsend made it 4-0.

Two changes were made to the Town side that made it five straight league wins with victory at Cambridge in midweek.

Skipper Craig Disley was rested, so Luke McCarthy came in on the left wing as Frankie Artus moved across to cover Disley's central midfield role.

The other alteration saw Pearson return at centre-back in place of the cup-tied Ian Miller, while Gary Silk kept his place at right back as Bradley Wood was forced to be content with a place on the bench on his return from suspension.

James McKeown began in goal, with Silk, Pearson, Scott Garner and Townsend forming the defence.

Michael Coulson, AndI Thanoj, Artus and McCarthy were the midfielders and the attack was unchanged, with Liam Hearn and Elding leading the line.

The Grimsby substitutes were Wood, Rob Duffy, Serge Makofo, Dayle Southwell and Charlie I'Anson, who had been absent since picking up an injury in the game at Lincoln City on Boxing Day.

Ryman Premier leaders Hornchurch made the long trip from London without their 19-goal top scorer Martin Tuohy, who was ruled out through suspension.

The Mighty Urchins did have players with experience at a higher level in their XI though, with attacker Tommy Black listing Arsenal and Crystal Palace among his former clubs and ex-Birmingham veteran Jonathan Hunt lining up in midfield.

Town's first opening came when Townsend found Hearn on the left side of the penalty area within 90 seconds and the striker got to the by-line but could not find a team-mate with his pull-back.

The Mariners began the game looking to keep possession and patiently build up attacks, while Hornchurch were also playing their part in a fast paced opening to the game.

Coulson was the first to test visiting keeper Joe Wooley with a drive from the edge of the penalty area on the right side that the stopper had to push out for a corner. From the flag, the Mariners opened the scoring as Coulson's pinpoint delivery was met by PEARSON, who headed home.

Townsend fouled Hunt to give the visitors a free kick on the right on 14 minutes but the ball in from the midfielder was eventually cleared.

Hearn then looked to have a good chance when he ran onto a through-ball from Townsend and looked to be pulled back before going down under a challenge as he aimed to shoot but referee Mr Bankes waved play on and the away side cleared.

A free kick was given when Artus was fouled just outside the box but Coulson's shot from it was blocked before defender Elliot Styles cleared.

Town kept the ball and worked it back into the danger zone, where a header from Garner was stopped by Wooley.

A Hornchurch attack then led to striker Lewis Smith firing high and wide from out on the left, with McKeown remaining untroubled in the Grimsby goal.

Town were dominating possession at the midway point of the first half but were guilty of giving the ball away in midfield on some occasions, letting their opponents launch counter-attacks.

The Mariners doubled their lead with a well worked goal just before the half-hour, when a long, deep cross by Silk on the right was volleyed back across goal by Coulson for ELDING to tap in at the opposite post to take his personal tally for the season into double figures.

Town were still playing a patient game, building up long sequences of passes and keeping the ball away from their visitors.

A chance for a third goal came on 35 minutes when Hearn found some space to hit a shot from the edge of the box that was blocked by Wooley, before Artus failed to make the rebound count.

Thanoj was spoken to by the referee after a foul on midfielder Simon Glover near the halfway line and the free kick from Hunt was headed clear by Pearson before a volley from the edge of the box was saved by McKeown.

Black, who had gone down easily throughout the half, thought he had a case for a penalty when he hit the ground again inside the Town box under a challenge on 41 minutes but again, the referee was not interested and play was allowed to continue.

Townsend was penalised for a foul on Frankie Curley a minute later, despite the protests from the Hull City loanee that he free kick should have gone his way. Hunt's kick from the right was pushed away by McKeown, before a curling shot from Black was caught by the keeper.

A short delay came when full-back Rickie Hayles failed to take a free kick given for a Hearn handball from the correct place but once the referee was happy with the positioning of the ball, the kick did not cause any problems for the Grimsby backline.

Two added minutes were played at the end of the half, with Hornchurch on the attack but again lacking a cutting edge up front to create any real chances.

Instead, it was Town who extended their lead further on the stroke of half-time, when another cross from Silk on the right found the unmarked ELDING, who cushioned a neat header past Wooley and into the corner of the net for 3-0.

That meant Grimsby took a commanding lead into the dressing rooms at the break, reflecting their dominance over the first half.

Duffy replaced Hearn in attack for the hosts before the restart as Rob Scott and Paul Hurst took the opportunity to rest their top scorer with a three-goal cushion already in place.

But it was Hornchurch who had the first opportunity of the second half, with Michael Spencer bursting through the middle and cracking a 25-yard drive that beat the dive of McKeown but hit the post.

The away side's lively start to the half continued when Spencer found Black down the left but the striker could not find a team-mate with a weak, low cross.

Grimsby's first attempt of the second period came when Spencer gave the ball away to McCarthy, who dragged his shot past the post.

A cross from Coulson on the right was then met by Elding but the striker, on a hat-trick, could only send a difficult back-header wide of the mark.

The away side's best chance so far came when Curley played a ball through for Smith but his shot was well saved by McKeown, at the expense of a corner.

Another seemingly golden opportunity came when Smith again found himself with the ball inside the box and showed quick feet to evade McKeown, before Town got bodies in the way to block the striker's shot.

The travelling supporters responded to their side's good start to the half, turning the volume up behind the Osmond Stand goal and even starting a conga around the stand, despite the three-goal deficit remaining in place on the pitch.

Black was replaced up front by Aaron Gayle for the visitors, before a good run from Townsend took him into the box, although his cross was headed clear before it could reach Duffy.

A cross from Anderson was headed out for a Hornchurch corner by Pearson but Hunt's delivery was too strong for any attacker to connect with it.

Thanoj picked up the first yellow card of the afternoon following a foul as the referee lost patience with the young midfielder, who had committed a number of infringements.

Thanoj was replaced soon afterwards as Scott and Hurst took the opportunity to play Wood in a midfield role as opposed to his usual slot on the right side of defence.

The Mariners made it 4-0 on 72 minutes with a great individual goal. TOWNSEND picked the ball up close to the touchline on the left and beat his man before cutting in and firing low past Wooley.

Hornchurch still refused to lie down and they won another corner soon afterwards, although the Londoners again failed to convert it into a chance in front of goal.

Spencer won another flag-kick off Silk and after Hayles was replaced by Andy Thomlinson, the corner was comfortably cleared.

Southwell was sent on in place of Elding as Town made their final change with 13 minutes left to play, before Les Thompson came on for Curley as the visitors also completed their substitutions.

Pearson cut out a cross from the right for another Hornchurch corner and the former Boston defender was involved again as he headed Hunt's delivery away from danger.

Town then closed the game out to keep a clean sheet, despite the efforts of Hornchurch to force a late consolation goal.

And with their £6,000 prize money and a place in Monday's third round draw secured, Grimsby now turn their attentions back to the league and the visit of bottom side Bath City to Blundell Park on Saturday.