Cross impressed from the bench in Scotland's first RBS 6 Nations win of 2014 against Italy last time out - replacing Moray Low before half-time with Johnson concerned over the Azzurri's scrum dominance.
In one of three changes made by Johnson for Saturday's clash with Les Bleus, tighthead Cross starts from the outset for the first time since Scotland's RBS 6 Nations victory over Ireland last February.
With Euan Murray recovering from a thumb injury to take his place on the bench however, Johnson is not short of tighthead options but he's urged Cross to seize his opportunity.
"I think it is the right thing to do. Geoff did really well in Rome against a formidable scrum but now it is a different challenge because he's starting the game," said Johnson.
"It's a big game for Geoff. He has been picked to do well at the set-piece and if he does that again we will be in a good position."
Johnson's other two changes come in the back row with Kelly Brown restored to the openside as captain with David Denton returning at No.8 - Johnnie Beattie shifts to the blindside in place of Ryan Wilson.
Brown's return means Chris Fusaro, who won his first two caps against England and Italy, drops out of the squad but Johnson predicts a bright future for the Glasgow Warriors flanker.
"Chris' endeavour was fantastic during his first two caps. I had a right good look back at the Italy match and you could see he won us some vital turnovers," added Johnson.
"He was exemplary in defence - his work was first-class - but he did get caught out positionally a couple of times and you get that with younger players some times. He accepts that.
"But it's the start of his international career and he now knows he can do it."