A switch in formation was the reason Gillingham chose to take Portsmouth loan man Haji Mnoga off at half-time on Saturday, said the manager.

Mnoga was put straight back in the starting eleven for the Gills against Mansfield Town, playing on the right of a three-man defensive unit. It was only his second game in a Gills shirt, his first lasting just nine minutes after being sent off on his debut.

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“I wanted to go to the back four,” said Harris, explaining his decision to take the youngster off at the break.

“I could have moved Haji to an out-and-out right-back and left Robbie McKenzie at left-back. I just felt that when you move to a diamond you need a bit of balance and we needed a left footer on that side of the pitch. I thought Robbie’s involvement has been really strong in a short space of time, it was Haji who had to come off.”

Plymouth loan man Ryan Law replaced Mnoga at the break. The Gills has started the game setting up 3-5-2 before reverting to 4-4-2 in the second half.

“We changed to diamond second half because that gave us more players in the middle of the park,” said Harris.

“When we went to Tranmere (where the Gills lost 3-0) with a back four against a team who get it forward and run after it, we weren’t good enough, so I thought three centre-halves was the obvious way to try and stop the forward-thinking threat (of Mansfield), we just didn’t stand up to it with three centre-halves on the pitch.

“We worked on the training pitch, video presentations, they knew what was to come, we knew Akins would link the play and Lapslie would run from a deeper position, it is not rocket science. For whatever reason the lads didn’t win the first contact, didn’t win the second ball, the third ball goes through and we are behind that as well.”

Gillingham didn’t make the most of their set-pieces at the weekend either, wasting some good opportunities particularly in the opening half.

Harris said: “They committed foul after foul around their penalty area to stop us getting in but then they were really good opportunities for us.

"We are a big side ourselves, the lads that took those deliveries were not to the standards that they have delivered in their careers.”