Pat Lam: This game is massive
And with only four Guinness Pro 12 fixtures remaining, neither coach is taking risks, naming their strongest available starting sides.
Connacht, never out of the top six this season, but facing three sides currently chasing play-off place, must make home advantage count if they are to grab that qualification spot ahead of Edinburgh or the Scarlets; Ulster, just two points off leaders Glasgow, and level on points with Munster, will not want to slip up if they are to make the semi-finals next month.