And Schmidt confirmed that Sexton's involvement will depend on the nature of his schedule with Racing.
"It forms some of the discussion I had with [Racing coach] Laurent Labit," Schmidt told the Irish Independent.
"Some of those decisions will be made later, but at this stage Racing are outside the play-offs, so he won't be playing in those three European weekends and will have those three weekends off.
"They have effectively five Top 14 games left and there is a mass of teams at the moment in the middle of the table.
"If they make the top six they will have a (play-off) match. If they get through that they will play right through until the end.
"If not, Jonathan may not have had that much rugby and it may be pertinent to bring him along."