This is the first game in seven months for the fit-again 27-year-old who joins Eoin McKeon and captain John Muldoon in the back row.
Galway-born forwards Ronan Loughney and Andrew Browne are promoted from the bench and represent the only other changes to the pack.
There is also a reshuffle to the back-line with scrum half Kieran Marmion the only player to be lining out in the same position as last week.
Darragh Leader, one of the westerners' try scoers against Ulster, has been named to start at full-back, while Ireland international Robbie Henshaw shifts to outside centre where he partners Eoin Griffin.
Wingers Matt Healy and Danie Poolman return to the starting line-up in place of Fionn Carr and Tiernan O'Halloran who has been ruled out with a quad tear sustained in training this week.
Miah Nikora is handed the reins at out-half and completes an all-Irish qualified fifteen.
Also ruled out this week is replacement hooker David Heffernan. With three hookers unavailable due to injury, the coaching team has had to call on the services of 19-year-old sub-Academy hooker Jack Dinneen.
The Limerick-born Dinneen, who now plays his club rugby with Galwegians and studies Commerce in NUI Galway, could earn his first senior cap against the Heineken Cup semi-finalists on Saturday.
Another notable addition to the bench is flanker Conor Gilsenan. On loan to Connacht for the remainder of the season, the 21-year-old lined out twice for the Eagles last month. If called upon, this will be his first PRO12 appearance.
Commenting on the team selection and the interprovincial clash, head coach Pat Lam said: "After a false start last week for Willie, it's great to have him back this week at the Sportsground.
"Seven is such a specialised position, and one which we've had to patch up this season with both Willie and Jake (Heenan) out long-term.
"It was obviously a big blow losing both Tiernan and Dave (Heffernan) to injuries during the week. Tiernan has been showing great form in the last two months but unfortunately this quad muscle tear has ruled him out for the rest of our season.
"We also had to train all week without Fionn, who has been struggling with a knee haematoma, so it is a complete reshuffle to the back-three. But what a great opportunity this is for the returning Danie and Matt who have been pushing the guys hard in training.
"It doesn't get any bigger than Munster at home. It's always a tough game for us no matter where we play them.
"It's been seven weeks since we've played at the Sportsground and with a huge crowd expected, it's certainly going to be a special night. We can feel the buzz in training, the buzz around town."
He added: "Everyone is up for it. But we know this is a 'must win' game for Munster too. Like us, they'll be hurting after their loss last week (against Glasgow).
"They will want to lay down a marker ahead of their big game with Toulon. We expect a big backlash and we need to be able to deal with it.
"We were so disappointed we didn't make anything of the opportunities we created against Ulster last week. We need to be so clinical on Saturday, especially against a side like Munster who don't give you many of those opportunities."
CONNACHT (v Munster): Darragh Leader; Danie Poolman, Robbie Henshaw, Eoin Griffin, Matt Healy; Miah Nikora, Kieran Marmion; Ronan Loughney, Jason Harris-Wright, Rodney Ah You, Michael Kearney, Andrew Browne, John Muldoon (capt), Willie Faloon, Eoin McKeon.
Replacements: Jack Dinneen, Denis Buckley, Finlay Bealham, Aly Muldowney, Conor Gilsenan, Frank Murphy, Dan Parks, David McSharry.