SYDNEY coach John Longmire has praised young forward Joel Amartey for his team-lifting nine-goal haul in the Swans' triumph over Adelaide, but justified his decision to pull the matchwinner off the ground late in the game and deny him the chance to kick a bag of 10.

Amartey found himself on the bench on two separate occasions late in the final term while stuck on nine goals, with Longmire admitting the move to put him on the pine hadn't gone unnoticed. 

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"He might have looked up (at the coaches box)," Longmire joked.

"But he's important and we want him available, once we had the game won it was important for the team that we looked after him and we got him into next week."

Amartey's four-goal second-quarter blitz brought the Swans back into the game after the Crows raced out to an early 23-point lead.

He didn't have a disposal to his name at quarter-time, but his four-goal second term was followed up by another four in the third to single-handedly flip the match on its head. 

He added another goal in the final quarter to finish with 9.1 from 10 disposals. 

"It doesn't happen much nowadays," Longmire said.

"He was so important for us tonight, his ability to take a grab and be a presence in front of the footy, but also to kick so accurately, it's such an important thing to do when you get the chance to be able to hit the scoreboard which he was able to do.

"You can see the team rising, he was huge and he was giving them the confidence to go forward when they could see that type of contest."

Amartey's previous personal best was four goals, but his nine-goal bag against the Crows boosted his season tally to 31 goals and has put him in the mix for the Coleman Medal.

Despite a three-game buffer at the top of the table, Longmire said there's still plenty of room for improvement for the all-conquering Swans.

"Every day we come into the footy club and we're trying to get better," he said.

"We've still got some improvement, and we're certainly pleased with what we did in the second half, but there's still some work to do in our game."

With their season on the line, the Crows brought the pressure early and had the ladder leaders on the back foot, leading by 23 points late in the second quarter.

After the Swans brought the margin back to four points at the main break, the Crows kicked away again in the third term and with six minutes to go, Sydney was still yet to kick a goal for the quarter.

But that all changed in the blink of the eye as the Swans kicked six unanswered goals to finish the term.

Adelaide coach Matthew Nicks said his side just wasn't able to go up another level after the Swans raised the bar.

"I thought we pushed and pushed them, the game was pretty even and in the balance and we actually got it to a point where we had some momentum with seven-odd minutes to go in that third quarter," Nicks said.

"Then they took it to another level and we didn't go with it ... they've done it all season and it's disappointing for us because we pushed them and took the game where we wanted to.

"In the end we get into the last quarter and we get three or four goals down, we're not here to lose by three or four goals we're here to try win a game of footy, so we open the game right up and try and take them on a bit with the ball but that's just like pouring petrol on the fire.

"They are a just a very, very good side."

The loss leaves Adelaide's finals dreams in tatters, consigning it to 15th spot on the ladder with a 4-9-1 ledger, and two-and-a-half games adrift of the top eight.