Sydney superstar Brodie Grundy has been helped off the field after suffering a scary injury in the dying stages of Saturday night’s thrilling two-point win over Brisbane.

With just over four minutes remaining, Grundy was crunched in a marking contest and was immediately in a lot of pain.

WATCH THE VIDEO ABOVE: Brodie Grundy helped off after worrying injury.

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As trainers and medical staff rushed onto the field to assist, the umpires quickly stopped the game.

One doctor had his hands on Grundy’s head and neck in worrying scenes.

“Grundy has not moved after getting crunched in a marking contest,” boundary commentator Alastair Lynch said.

“He’s moved his right hand and that’s about it.”

Former Collingwood coach Nathan Buckley recounted a similar incident involving Grundy during his time at the Pies.

“He went down at training at one stage with the Pies and had to be taken to the hospital with his neck. They are holding him in that position now,” Buckley said.

“Maybe a stinger, he was moving his hands so maybe he got a bit of a nerve shoot down there.”

But after about a minute, Grundy was able to get to his feet and slowly come from the field.

“That’s great vision for me given I’ve seen him in that position before and it didn’t end well,” Buckley added.

Grundy played no further part and had an HIA, but was given the all clear.

He will continue to be monitored over the coming days.

The 31-year-old has been one of the best players over the past two months, surging into All-Australian contention.

In another blow, Justin McInerney suffered a knee injury that will end his season early.

The Swans survived an almighty scare with the Lions slamming on three goals in the last two minutes to nearly pull off the greatest of comebacks.

However, their run was too late with the final goal coming with just four seconds remaining.

The loss could have major implications on Brisbane’s top-four hopes, as they could fall down to fifth ahead of a tough final fortnight against Fremantle and Hawthorn.

In fact, they could miss the eight altogether if they lose their final two matches.

Meanwhile, Sydney star Isaac Heeney equalled his career-high with five goals in the two-point victory.

The Swans flipped the script in the grand final rematch, running freely through a Lions midfield missing injured star Lachie Neale and moving to 11-10.

Tough Brisbane defender Brandon Starcevich (hamstring) was also a late out.

It left coach Chris Fagan without four of his grand final backs, with Jack Payne (knee), Noah Answerth (achilles) and Ryan Lester (concussion) also on ice.

But the lack of pressure, particularly at the Gabba where they’re now 6-4 this season, and wayward kicking have been a consistent theme regardless of personnel.

That was to blame again, Sydney shooting to a 19-point lead in an end-to-end first quarter that featured just 16 tackles and few stoppages.

The Swans backed their pace through the centre of the Gabba, shrugging would-be tacklers and sharing the goals.

Lions defender Darcy Wilmot stopped the rot before the first break with a goal against the run of play.

His second in similar circumstances was the Lions’ fifth straight as they jumped 11 points clear.

But Heeney led the Swans’ response, snapping his second and third goals off his left boot and then soccering through a fourth after another sloppy Lions turnover.

When Heeney earned a free kicked and equalled his career high of five goals the margin was 20.

The Lions bombed another chance and it started getting ugly when Sydney sliced them up twice more to make it seven straight Swans goals.

Levi Ashcroft broke the run and Henry Smith’s brilliant solo effort, tapping to himself and snapping a goal, brought it back to 20 points.

A Zac Bailey set-shot miss took some wind out of their sails at three-quarter time, the Lions again missing the mark on an early fourth-quarter chance.

Grundy then twisted the knife with a goal when he went forward.

The Lions accumulated costly misses before Morris’s third, a late Bailey double and another goal straight from the bounce flattered the scoreline in a manic final 60 seconds.

Lions midfielder Josh Dunkley (31 disposals, seven tackles, six clearances) was a bright light in Neale’s absence while Errol Gulden (29 disposals) led the Swans.

- With AAP