Buxton were leading 1-0 before James Hurst’s 30th minute red car turned the game around.
"People talk about the red card being vital but I still think we'd got too much for them on the day,” he said.
"Let's face it Buxton's had two worthwhile shots throughout the game. I thought we were a bit passive early on but then we took the game to them.
"We tweaked one or two things in the second half putting them on the back foot and I think it would have been unjustified had we not won."
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The Matlock boss admitted though that he and the players had spoken at length about the importance of staying disciplined in a derby in the lead-up to the game.
He added: "For me staying disciplined was vital in a big derby in front of a big crowd where expectations are high, discipline could either win you or lose you the game.
"I thought the referee managed the game really well. We wouldn't have wanted Buxton to have the lad sent off we'd have liked it eleven versus eleven."
Matlock now head to 17th placed Gainsborough Trinity on New Years Day and Phillips wants his side to make it three league wins on the trot and not waste the efforts of the Buxton game in reaching the summit.
The Gladiators beat the Holy Blues 3-0 on August Bank Holiday Monday and while their away form has been generally poor with only five points from thirty three on their travels, at home Trinity have lost only once, drawing six and winning five.
"They're a good side and we're expecting a hard game,” adde Phillips.
"We're going to enjoy Monday's win but it doesn't define anything in terms of winning anything.
"This is one of a number of tricky games we face in January, we got a good derby win but we don't want to blow it all away.
"We know we're there to be shot at but that's credit to the lads, when you look at the massive financial backing that South Shields and Buxton get. It's to the boys' credit that we're well in there with a shout, people would have thought me mad a few months ago if I'd said we'd be top of the table at Christmas."