Super Rugby Aus starts on Saturday in Brisbane and there will be immense interest in how both fare ahead of next year's World Cup on home soil.
Lynagh, the starting flyhalf in all three British and Irish Lions Tests last year, managed just 18 minutes for the Reds because of a series of injuries last season.
All going to script, he will get at least 40 minutes against the Force at Ballymore in new Reds coach Vern Cotter's first game in charge since his historic move from Auckland's Blues to replace Les Kiss.
Lynagh's return comes as Reds teammate and flyhalf Carter Gordon enters two months of rehabilitation after fracturing his fibula in last weekend's Test draw against Argentina in Mendoza.
Gordon had established himself as the Wallabies' first-choice No.10, leaving Kiss with some big calls ahead of a clash with South Africa and a two-Test Bledisloe Cup in the next six weeks.
"I'm really enjoying Tom in a playmaker role," Cotter said of the son of former Wallabies great Michael.
"He's got a great head on his shoulders, he sees the game well, he's calm and decisive.
"With the niggles he has had, we will probably be a bit careful with him, so it probably won't be 80 minutes, but certainly a good 40 minutes to start with.
"He's a great player in organised play but brilliant at unstructured (play).
"It's a good opportunity for Tom to get out there and boss the team around. ... pull a few strings and get some combinations."
Harry McLaughlin-Phillips, released by the Reds to join the Force this season, will oppose Lynagh and consider himself in the thick of Wallabies discussions after being part of their training camp earlier this year.
Kurtley Beale has been named on the bench for the Force, but new signing James O'Connor, another sure to be in Kiss's considerations, will not play.
Lomax, an Australian and NSW State of Origin rugby league winger, revealed this week he would be deployed in the No.13 against the Reds.
A dominant showing there would add intrigue to Kiss's midfield selection headache after fellow code-hopper Joseph-Aukuso Suaalii's struggles to nail down the jersey in 24 Tests.
Japan-bound fullback Jock Campbell, replaced in the No.15 by Tom Wright after one Test in July despite a good showing against Ireland, will also get a chance to show something when he comes off the bench for the Reds.
Fellow Wallabies Matt Faessler, Zane Nonggorr and Josh Flook have been named, while Australian under-20s captain Tom Robinson will wear the No.6, and exciting fullback Will McCulloch will start.
NSW Waratahs lock Miles Amatosero, red-carded in his second Test appearance in Osaka, will mount his comeback against the ACT Brumbies on Sunday in Bungendore, east of Canberra.
Teddy Wilson and Max Burey, after earning an early release from the Force, will partner in the halves, while Sid Harvey will start at fullback.
Triston Reilly will wear the Brumbies' No.15 against his former club a week after piloting the First Nations and Pasifika XV to victory in Tonga, while Wallabies wing aspirant Corey Toole will add pace on the flank.
