Flanker Ray Ofisa (vertigo) and centre Keith Matthews (ankle) have been ruled out through illness and injury respectively, while Conor Higgins is included in the extended squad as cover for prop Robbie Morris, who is nursing a calf injury.
The Connacht team and replacements to play Toulon will be announced on Thursday.
All tickets have now been sold for Friday's massive clash with the French side at the Sportsground.
The final batch of tickets for the game was sold on Wednesday morning and Connacht Rugby is grateful to the people of province who are supporting them in such great numbers for this big game.
Connacht coach Michael Bradley said: "A semi-final of a European Cup competition is a great event to be involved in, a special day for our supporters and the squad and management, and to have that event in Galway is huge.
"The match is a sell-out which is an excellent back drop to the event itself. We see it as a great opportunity to continue our good form in Europe.
"We're unbeaten in Europe to date - the only unbeaten team in Europe this season, in fact. It could be an historic season for us if we get to the final and/or win it. So, all those things are going on the table on Friday night."
Connacht CEO Gerry Kelly added: "The support from people and businesses throughout Connacht has been a source of great encouragement and it promises to be a great occasion at the Sportsground.
"We very much appreciate the great support we are getting and hopefully we can deliver the right result on Friday.
CONNACHT Squad (v Toulon) - Backs (10): Fionn Carr, Gavin Duffy, Ian Keatley, Frank Murphy, Troy Nathan, Miah Nikora, Conor O'Loughlin, Niva Ta'auso, Brian Tuohy, Aidan Wynne.
Forwards (14): Sean Cronin, Adrian Flavin, Jamie Hagan, Conor Higgins, Ronan Loughney, Mike McCarthy, Mike McComish, Robbie Morris, John Muldoon, George Naoupu, Johnny O'Connor, Michael Swift, Bernie Upton, Brett Wilkinson.