The host operated with reduced numbers for more than an hour of the contest after David Ball was given a deserved straight red card for a reckless lunge on Matt Simon.
Simon recovered well enough to give Central Coast the lead five minutes before half-time, clipping home Marco Urena's excellent throughball.
The goalscorer heaped praise on the experienced Costa Rica playmaker afterwards.
"You can see Marco's quality out on the pitch and that pass was just another showing from him of how good he is," Simon said.
"And he's only going to get better. I think he's still got a little bit to go to get 100 per cent fit but I think he's shown his qualities so far."
Oliver Bozanic made it 2-0 from the penalty spot after another misguided Phoenix challenge - this time from Te Atawhai Hudson-Wihongi on Daniel De Silva - and there was little doubt from that point that the Mariners would open up a four-point gap over second-placed Macarthur.
Brisbane Roar had the chance to leapfrog the Sydney club but was held to a 0-0 draw at home to Newcastle Jets.
The Jets are seventh with two wins from eight games so far, with Valentino Yuel close to a being a topical matchwinner on Sunday when his 25-yard drive boomed back off the post.
Wellington are only kept off the bottom by Melbourne Victory on goal difference, although they have only played six times.