In-form John Marquis took his tally to five goals in three games with a brace in Portsmouth’s 4-0 demolition of lowly Northampton.

Ronan Curtis and Marcus Harness were also on target as Kenny Jackett’s men picked up their third win in eight days.

The hosts had a big let-off in the 16th minute when Ryan Watson blazed wide after finding himself clean through.

Marquis made Watson pay for his miss six minutes before half-time with a poacher’s finish after Ryan Williams had seen his initial shot saved.

Striker Marquis had a chance to double his tally two minutes later but was denied by Northampton goalkeeper Jonathan Mitchell.

It took Marquis just two minutes of the second half to find the net with another follow-up effort after Mitchell could only parry Curtis’ header.

Curtis put the game out of Northampton’s reach in the 50th minute with a perfectly-placed strike from the edge of the penalty area.

Harness’ header from an Andy Cannon cross seven minutes from time completed the rout.