Just as Bengals rookie receiver Mohamed Sanu was emerging as a major presence in Cincinnati’s offense, he may have been lost for the season.

Bengals coach Marvin Lewis said today that Sanu has a stress fracture in his foot that will require surgery, and that Sanu might not be able to play again until next year.

That’s a bigger blow to the Bengals’ offense than Sanu’s numbers might suggest. Although Sanu has caught only 16 passes this season, the Bengals were increasingly relying on him in recent weeks, especially in the red zone, where he scored four touchdowns in the Bengals’ last three games.

A third-round pick in this year’s NFL draft, Sanu took some time to get going in the Bengals’ passing attack, but has now caught at least two passes in five straight games. The next pass he catches may be in September of 2013.