In the pack, Darren Morris makes way for Tevita Taumoepeau at loose-head prop, with Aleki Lutui replacing Chris Fortey at hooker, Tim Collier starting for Phil Murphy at lock, and Tom Harding returning in place of Drew Hickey in the back row.
Murphy, Morris and Fortey take their places alongside scrum-half Ryan Powell on a bench that also features the welcome presence of Gavin Quinnell.
The 23-year-old has worked exceptionally hard with Bob Stewart and Keir Hansen's physio and conditioning teams to make a startling recovery from a nasty-looking knee injury sustained against Newport Gwent Dragons just three weeks ago.
"This Christmas and New Year period is all about managing recovery," Brain says. "The ideal scenario is that no one player should start more than two games, but, obviously, there are circumstances that dictate that a player might have to start all three."
The last remaining tickets for tonight's match sold out before 1pm.
Team: 01 Tevita Taumoepeau, 02 Aleki Lutui, 03 Chris Horsman, 04 Craig Gillies, 05 Tim Collier, 06 Pat Sanderson (c), 07 Tom Harding, 08 Kai Horstmann, 09 Matt Powell, 10 James Brown, 11 Marcel Garvey, 12 Thomas Lombard, 13 Dale Rasmussen, 14 Aisea Havili, 15 Thinus Delport
Replacements: 16 Darren Morris, 17 Chris Fortey, 18 Phil Murphy, 19 Gavin Quinnell, 20 Ryan Powell, 21 Shane Drahm, 22 Mark Tucker