England vice-captain Lawes ruled out of Six Nations game against France
Lawes has endured a tough time since he won the last of his 96 caps for England in Australia last July, with concussions, neck, buttock and calf injuries limiting him to only four games this season for his club Northampton, who on Friday revealed the player will undergo surgery.
"Following consultation between the club's medical staff and a specialist, Courtney Lawes will undergo surgery on the pectoral injury he sustained in England training last week," Northampton said in a statement.
Head coach Steve Borthwick named his 27-man squad for Saturday's clash, with David Ribbans replacing Lawes and Marcus Smith the main new addition after George Ford was left out.
Ford trained with the squad in Smith's absence last week as the twin-playmaker was released from training for game time with his club Harlequins.
Smith came on late in Saturday's win over Wales, after another appearance off the bench against Italy, as Borthwick installed captain Owen Farrell as his flyhalf.
England host France before finishing their Six Nations campaign in Dublin a week later.