There wasn't much in the game before half time but 52 minutes in the Lilywhites opened the scoring, trialist Jamie Thomas nodding home.
Accy levelled through Joe Pritchard after 67 minutes and but for some excellent saves from Declan Rudd, could have had more.
Riis started the game up front alongside Sean Maguire. After having some time off over the summer the focus for the Dane is to get back to full fitness.
He said: "We wished for a better result but getting minutes in the legs is what it's about.
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"They're a tough team, a strong team so we knew it'd be physical but it's just about getting those minutes into the legs and getting comfortable in the team.
"We're three weeks into pre-season and we still have two more weeks until the first game."
Riis' eyes are firmly on the prize, as the opening game of the 2020/21 Championship season draws nearer.
PNE host Hull City on August 7 as they kick off the campaign, a day that is already on the mind of the 23-year-old.
"We're just building up for the Hull game and week by week we get closer," he said.
"There are things to improve on, we've had seven weeks off and it's only natural that there is stiffness.
"We need some game time to come back into but that's what pre-season is for and we get closer each week.
"It's important to get your fitness back, you give yourself a rest because you're playing for 10 months and your body feels it."
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