Guiseley were defeated late on against a Macclesfield Town side who were clinical with minutes to go, writes Tom Feaheny.
The result means the Lions remain in the relegation zone, ahead of facing Maidstone United tomorrow.
"It sums up our season, the first goal conceded is a lack of concentration, we then give Durrell too much time and space, he took his goal well, we have switched off twice and been punished by a good side," Cox said.
"We have faced a few fair sides we have faced have gone top after facing us, Maidstone won't be an easy game, we know their strengths and we will have to perform at a high level to gain that win."
One big positive for Guiseley on Tuesday was the debut of Mike Fondop who impressed Cox with his goal and looks to have made a good first impression.
"Mike brings power, pace and directness, he impressed in a trial game, we need to get an understanding of his strengths, he took his goal really well, deserves credit for what he has done."
"We are looking to add to the squad, bring players in, the pressure is on the players now to impress, they need to relish that, I expect to be able to bring more in."
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