Pittsburgh Steelers head coach Mike Tomlin has admitted that the latest injury suffered by outside linebacker LaMarr Woodley is "unfortunate" for his side.

Woodley was placed on season-ending injured reserve after picking up a calf strain early in his side's 30-20 win over the Cincinnati Bengals on Sunday.

The 29-year-old has already missed 12 matches through injury since 2011, and Tomlin acknowledged that the Pro Bowler's injury woes had begun to grow in recent years.

"He's been solid, not only this season but over the course of his career. But obviously, particularly in recent years, he's had to battle some injuries, unfortunately for him and for us," Tomlin told reporters.

Woodley, who is seventh in the Steelers' all-time sacks list with 57, is likely to be replaced in the starting lineup by rookie Jarvis Jones.