Saints safety Kenny Vaccaro logged onto his Instagram photo sharing application account Monday and said he will miss Sunday's home game against the San Francisco 49ers with a concussion.

"Mad I can't play this weekend," a message on Vaccaro's account read. "We will take care of business."

NFL Network's Ian Rapoport reported earlier in the day that Vaccaro would sit out the contest against the Niners (6-3) and could miss the following week of action as well. At his Monday meeting with the media, Saints coach Sean Payton refused to discuss Vaccaro's status and called a question about the player's health "dumb."

Vaccaro's helmet hit Cowboys tight end Jason Witten's knee as the Saints rookie made a tackle late in the third quarter. Witten gained 19 yards on the play; and after the collision, Vaccaro left the contest, which New Orleans (7-2) won 49-17.

Vaccaro also suffered a concussion in the Oct. 27 win at home over the Buffalo Bills when he collided with cornerback Keenan Lewis in an attempt to break up a pass. That injury didn't cause him to miss a game.

Vaccaro has lined up for the Saints on 502 defensive snaps, the most on the team, according to analytics website Pro Football Focus. He has 56 tackles (41 of them solo), one interception and one sack, and he is considered a contender for the NFL's Rookie of the Year Award.

The Saints suddenly may be thin at safety. Roman Harper has been inactive since after Week 2 with a hurt knee, and Malcolm Jenkins missed the Cowboys game and the Nov. 3 loss at the New York Jets with the same.

Aside from Harper, Jenkins and Vaccaro, the Saints have Rafael Bush and Isa Abdul-Quddus. Chris Carr plays a hybrid cornerback/safety role.