Everitt, who has racked up 238 points for the Exiles so far this season, makes way for Mark Mapletoft, who replaced him during the second half of the match against Leeds on April 20.
In all, there are three changes to the starting line-up of the team that faced the Tykes, with Kevin Barrett starting on the left-wing in place of Geoff Appleford who moves to outside centre.
Meanwhile, Rob Hoadley replaces the injured Brendan Venter at inside centre.
Commenting on the selection, Conor O'Shea, Managing Director of relegation-threatened London Irish, said: "The injury problems that have haunted us all season continue. Nine of our senior players are unavailable. We have decided to retain Mark Mapletoft at fly-half where his experience will be invaluable to the team in Brendan Venter’s absence."
Unavailable for selection through injury were Justin Bishop (ankle), Kevin Burke (knee), Nick Burrows (knee), James Cockle (finger), Glenn Delaney (ankle), Darren Edwards (ribs), Paul Gustard (torn biceps), Richard Kirke (shoulder) and Venter (knee).
London Irish: 15 Michael Horak, 14 Paul Sackey, 13 Geoff Appleford, 12 Rob Hoadley, 11 Kevin Barrett, 10 Mark Mapletoft, 9 Hentie Martens, 8 Chris Sheasby, 7 Kieron Dawson, 6 Declan Danaher, 5 Bob Casey, 4 Ryan Strudwick (captain), 3 Rob Hardwick, 2 Naka Drotske, 1 Mike Worsley.Replacements: 16 Kevin Brennan, 17 Barry Everitt, 18 Nick Kennedy, 19 Adrian Flavin, 20 Kieran Roche, 21 Neal Hatley, 22 Simon Halford.
Kick-off: 14.00 BST (13.00 GMT)