You are not permitted to download, save or email this image. Visit image gallery to purchase the image.
Toomua missed last round's disappointing loss to the Sharks in Ballarat due to a groin injury but has returned to relegate five-eighth Andrew Deegan to the bench.
Among the inclusions, Wallabies hooker Jordan Uelese has been named on the bench for his first match of the season after suffering a hamstring injury in January.
Rebels defence coach Kevin Foote said they were thrilled to have 23-year-old Uelese back in the line-up after he also missed most of the 2019 season with a knee injury before making the World Cup squad.
"It's really special for Jordan, who is coming back from injury after the World Cup," Foote said.
"He's a big body and a really good scrummager and set piece forward so it's good to add that depth to the squad."
Foote said they were still smarting from the 12-point loss to the Sharks, which came after a rousing breakthrough win over the Waratahs.
He said the Brumbies' last round win over the Chiefs in Waikato had given them confidence of upsetting the Highlanders to post a rare win on NZ soil.
"The Brumbies were awesome - they had some setbacks and we did too with some late injuries - but the Brumbies showed some real grit to go over there and do a job," Foote said.
"We want to go to Dunedin and keep flying the flag for Australian rugby."
Rebels: Dane Haylett-Petty (capt), Andrew Kellaway, Tom English, Billy Meakes, Marika Koroibete, Matt Toomua, Ryan Louwrens, Isi Naisarani, Richard Hardwick, Angus Cottrell, Matt Philip, Gideon Koegelenberg, Jermaine Ainsley, Anaru Rangi, Matt Gibbon. Res: Jordan Uelese, Cameron Orr, Cabous Eloff, Ross Haylett-Petty, Rob Leota, Frank Lomani, Michael Wells, Andrew Deegan.