The Pilgrims travel to second-bottom Guiseley on Saturday looking to close the gap on the play-off spots, currently trailing York City by five points.
"This club shouldn't be in a position of mediocrity, and what I mean by that is - at the minute we're ninth," Cox said, demanding his players put that right.
"Still loads to play for. But if we carry on as we have done in the vein of this season we'll finish as we have (been). We'll finish 10th, 11th, 12th, that's what the stats are suggesting.
We need to wake ourselves up. We've got loads to play for."
Cox also dismissed suggestions he is a long-ball manager.
With former Sheffield United target man James Hanson likely to start against his former club this weekend, the United boss knows it would make sense to play to his strengths, but knows this isn't the only option.
"I hear some of the stuff spoken about my teams and it makes me laugh," he added.
"I've never told a team to go forward and play long ball.
"If it's on, get it in good positions. We've got a 6'4" boy who's experienced and great at knocking the ball down for the second striker.
"But you can't just boot it from back to front, there needs to be a bit of quality.
"We've got loads to do as a side and it might might surprise a few people. It's my job to sort that in the business end of the season."
New signing Brad Nicholson could also feature against his former club.
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