The Reds were one man down for more than 70 minutes, with Ersan Gulum controversially sent off on 18 minutes.

Trailing 2-0 just before the hour, the home side fought heroically to grab a share of the spoils.

The first half was littered with controversy as the Video Assistant Referee (VAR), or lack thereof, again became a talking point.

While the Mariners settled quicker, they took an unexpected lead after just seven minutes following the first of two game-defining decisions.

Referee Shaun Evans awarded them a free kick on the edge of the area for a foul on Andrew Hoole by Isaias, despite the ball clearly striking the hand of the attacker in the build-up.

Hoole wrong-footed Reds keeper Paul Izzo, sending him the wrong way.

Ten minutes later, the game was turned on its head when Gulum was given a straight red card.

Hoole was again involved, sending speedster Trent Buhagiar through on goal with a defence-splitting pass.

As Buhagiar sped past Gulum, he made contact and the attacker went tumbling.

The contact was minimal but referee Evans had no hesitation in giving the Reds' stopper his marching orders.

The VAR didn't review the incident as the United camp and home crowd fumed.

Central Coast tried to exploit the advantage with Hoole and Jacob Melling testing Izzo from distance, while Alan Baro forced a stunning stop from the Reds' keeper at close range.

After the break, the Reds had a couple of early chances through Nikola Mileusnic and Ben Garuccio.

But, Central Coast doubled their advantage, courtesy of Ryan Strain who inadvertently headed into his own net.

The home side pulled a goal back on the hour when Jordan Elsey rose highest to head home a teasing free kick from Garuccio.

The 10 men of United continued to push for a leveller and, after a couple of near things, young striker George Blackwood smashed home a half volley with seven minutes left.

Teed up by Adlung, Blackwood controlled with his thigh before slamming his shot past Kennedy.

After a gruelling 90 minutes, Adelaide coach Marco Kurz said his side fully deserved a point.

"I said to the boys: 'have belief, have confidence'," he said.

"I was 100 per cent sure we had enough power until the end to get the turnaround," he said.

Mariners coach Paul Okon lamented Central Coast's inability to keep their lead with a one-player advantage.

"When you score two goals here and you're leading 2-0 with 20 minutes to go, you expect to win the football game," he said.

"(It's) real disappointing."

Australian Associated Press