The 25-year-old was competing in the 5000m event at the Box Hill Burn meet where he was trying to break both the 13-minute barrier and Craig Mottram's national record of 12:55.76 which was set in London back in 2004.

McSweyn quickly slotted into third spot after the start, sitting behind pacemakers Adam Spencer and Jordan Williamsz until Spencer dropped out with nine laps to go.

Williamsz did likewise with six laps to go, leaving McSweyn by himself as he sat just outside record pace but inside sub-13 minute pace.

Things appeared to still be on track with three laps to go as the crowd lined the outside lanes of the track to cheer him on, but he fell away slightly over the closing stages, winning the race in 13:05.87.

That time was still good enough to see him set the fastest time in Australia over the distance since the 2006 Commonwealth Games, record the fourth-fastest time ever on home soil and set the second-fastest time by an Australian in the country.

In a post-race interview on Athletics Exclusive, McSweyn said it was tough going as the laps counted down.

"It was an awesome atmosphere and a good night for running," he said.

"I gave it a good crack and was on pace to get that record after three kilometres, but probably over the last 2-3 laps it was a pretty hard slog.

"But the effort was there and I'm pretty happy with how it turned out."

The time was also only 0.64 seconds outside McSweyn's personal best for the trip in just his second race for the 2021 season and gives him another Olympic qualifying time to go with the marks he set for the 1500m and 10,000m distances.

"I'll just go back to training now and the big focus from here is the Olympics," McSweyn said.