Sydney led the red-hot Pies by ten points in the last quarter at the SCG on Friday, but the visitors executed better down the stretch to win 80-73.

Key forward Sam Reid retuned to form with an equal career-best haul of six goals, but Sydney lost midfielders Josh Kennedy (medial ligament knee injury) and George Hewett (head knock) in the second half.

Asked about co-captain Kennedy's injury, Longmire said, "we'll have to wait and see but it's definitely a few weeks (out) I'd say".

For the second straight SCG game co-captain Dane Rampe had a moment to forget late in the contest.

After climbing up a goalpost at the death against Essendon two weeks ago, the key back gave away a critical 50-metre penalty, from which Chris Mayne kicked the clinching goal from right in front.

Collingwood led by just two points with three minutes to go before Mayne's initial attempt looked set to be recorded as a behind.

However Rampe was called for stepping over the mark just after the ball left Mayne's boot and he was given a second, easier opportunity.

"He (Rampe) has been incredible this season as a key defender and he very rarely gets beaten, he's just such a competitor, he gets most things right, not all things right," Longmire said.

'He played well, but he shouldn''t have did what he did in that last bit."

Longmire said Reid played as well as he'd ever seen, but felt he benefited from the return of Sydney's other veteran key forward, Lance Franklin, after a four-week hamstring injury.

While Franklin had just six touches and kicked only two goals, his presence ensured Collingwood couldn't gang up on Reid.

"Lance played a lot more minutes than what we expected or planned because of the two injuries but he was able to essentially let Reidy go about his business," Longmire said.

He praised the tagging effort of Ryan Clarke on Steele Sidebottom, who had just 13 touches - half his season average and his lowest single game tally since 2013.

Sydney have dropped to 3-7, but Longmire couldn't fault his charges.

"I still reckon we took a step forward," he said.

'We didn't win tonight but we still got a lot of stuff right, we were really happy with a lot of the things that we did.

"Next week we play (ladder leader) Geelong. What a great opportunity for these young blokes to keep going."

Australian Associated Press