The Chiefs' most capped player will win his 150th cap for the franchise he's played for since 2006, when he starts at blindside flanker in round six of Super Rugby.
No 8 Michael Leitch returns from his one-match suspension to join Messam and Sam Cane in the back row; Siegfried Fisi'ihoi replaces Kane Hames (minor ankle knock) at loosehead prop as the forward pack shuffles for Saturday night's battle with the Bulls.
Messam turned 33 this month but Chiefs assistant coach Andrew Strawbridge believes the 43-cap All Black is fitter than ever and well set to win even more caps.
"In our programme, I've talked about how wonderful it is to have Liam back in our environment and what a difference he makes and what a great leader he is, particularly in helping young men understand the edge you need to cope at this level," Strawbridge said.
"He's in really good nick, he's fit and he's still working hard on aspects of his game. We're still helping him improve, so I could see him add to his 150."
Messam is driving a campaign to raise money for two-year-old Ka'iulani Forbes, who is battling stage four high risk neuroblastoma, which means he and his Chiefs team-mates - including Mitch Karpik - have shaved their heads this week to aid the Forbes family in paying for the medical treatment Ka'iulani requires abroad. It could cost up to $2million.
The Chiefs prepare for the Bulls after a close shave against the Rebels in Melbourne in round four, where they snatched a 27-14 bonus point victory that left players and coaches with plenty to ponder during their bye week.
"We're not happy with the way the Rebels game went and it was a less than satisfactory performance from our team," Strawbridge said, before adding that subsequent changes were made based on that sloppy showing against the Rebels.
Aaron Cruden, James Lowe and Johnny Faauli are reinstated to the starting XV, with the latter partnering Anton Lienert-Brown in the midfield.
It will be Faauli's third start at second five-eighth in his debut season in Super Rugby, in a position the Chiefs have chopped and changed.
Chiefs coaches have liked what they've seen so far from the Taranaki centre, who Dave Rennie has described as a 'mini Ma'a Nonu'.
"He's done pretty well with the opportunities he's had," Strawbridge said.
"We see him as a fairly abrasive customer and we like what he gives us around go forward.
"He gives us a bit of belligerence and we're trying to extend his game; round it out a bit more and you can't do that if you don't give guys opportunities."
Damian McKenzie switches back to fullback and Shaun Stevenson moves to the right wing, with Toni Pulu not risked as he bids to prove his fitness before the Chiefs fly to Africa on Sunday.
Pulu's hamstring injury is minor but he's not been running at full speed in training this week, so Northland winger Solomon Alaimalo could win his second Chiefs cap off the bench.
Loose forwards Lachlan Boshier and Mitchell Brown won't feature as Taleni Seu returns to the bench that includes hooker Brayden Mitchell, who will make his Chiefs debut if he plays.
AT A GLANCE
What: Chiefs v Bulls
Where, when: FMG Stadium Waikato, Hamilton on Saturday at 7:35pm
Chiefs: Damian McKenzie, Shaun Stevenson, Anton Lienert-Brown, Johnny Faauli, James Lowe, Aaron Cruden (co-c), Tawera Kerr-Barlow; Michael Leitch, Sam Cane (co-c), Liam Messam, Brodie Retallick, Dominic Bird, Nepo Laulala, Hika Elliot, Siegfried Fisi'ihoi. Reserves: Brayden Mitchell, Kane Hames, Atu Moli, Taleni Seu, Mitchell Karpik, Finlay Christie, Stephen Donald, Solomon Alaimalo.
Photo by: Bruce Lim / www.photosport.nz (Liam Messam will win his 150th Chiefs cap against the Bulls).