Campbell excelled in a wet edition of the 12 Hour to steer his Manthey Racing/EMA Motorsport Porsche 911 GT3 R to the chequered flag alongside co-drivers Ayhancan Guven and Laurens Vanthoor.

Two-time defending champions Kenny Habul, Luca Stolz and Jules Gounon finished second in their Sun1Energy Mercedes while the Melbourne Performance Centre Audi of Christopher Haase, Kelvin van der Linde and Liam Talbot made up several spots in the final laps to finish third.

After starting the race from fourth on the grid Campbell, Guven and Vanthoor were consistently the fastest drivers on the grid, and looked just as dominant when the rain began to fall in the back half of the race.

The only blemish on a strong day for the winning Porsche was a drive through penalty for not meeting the minimum pit stop time.

That wasn't going to be enough to stop Campbell from climbing back to the top, as he added to his 2019 success in the 12 Hour with Earl Bamber Motorsport.

"The car was phenomenal all day, both in dry and wet conditions. It looked a little tough there during one of my last stints when we got the drive-throughs but luckily enough we were able to come back through the field

"The team did a fantastic job with the pit stop when the rain started to come down. That really turned our race back around after a down moment in the hour before.

"It was a crazy race. We had fantastic speed all day. I must say that Laurens and Ayhancen did a fantastic job, and hats off to Ayhancen with it being his first time here and in the wet.

"It's a team effort so a huge thanks goes to everyone and EMA and Manthey Racing."

The race went for almost three hours before the first safety car was required.

One of the biggest casualties during the race was the pole-sitting #32 Team WRT BMW.

Charles Weerts was attempting to overtake lapped traffic but clipped the rear right of the #56 Ginetta G56, sending his BMW into the outside wall and out of the race.

The rain then arrived at the halfway mark, forcing teams to rethink their strategies and take things cautiously in challenging conditions.

Several top 10 contenders had their winning hopes dashed inside the last two hours.

Daniel Juncadella was behind the wheel of the #77 Craft Bamboo Mercedes when he contacted the wall at Reid Park, while the #2 Melbourne Performance Centre Audi of Markus Winkelhock was forced into the garage with a persistent mechanical issue.

With 50 minutes to go the frontrunning entries had all completed their final stops and Matt Campbell emerged from pit lane with a 20 second advantage over Gounon in the defending champion #75 Mercedes.

That advantage was quickly wiped out when Julien Boilot accidentally beached the #701 Chevrolet entry on the Griffins Bend kerb.

The incident forced the safety car to make one more appearance and led to one last 30 minute period of green flag racing.

With 15 minutes to go Gounon was trailing Campbell by two seconds before he and the train of pursuers were held up by lapped traffic, which pushed the gap beyond six seconds and effectively secured the result.