Ryan Seacrest talks to Rihanna's breasts on the Grammy red carpet.

Ryan Seacrest spots Rihanna’s nipple and stud on the Grammy red carpet.

Rihanna breezed past CBS Grammy Awards censors, even though her stunning Azzedine Alaia dress was sheer enough to see her nipple and protruding nipple stud. Ouch!

The dress drew wide praise in reports afterward. It highlighted her toned upper body while seemingly covering her appropriately as per CBS guidelines on Grammy night dress.

Under the bright lights illuminating the red carpet and in the flashes from photographers’ cameras, however, the dress was almost totally see-through.

Rihanna seemed oblivious to the fashion faux-pas, but Ryan Seacrest certainly caught it. In one screen-capture from his televised interview he can’t take his eyes off her breasts.

Rihanna’s Steamy Red Azzedine Alaia Gown

For the first time in memory, the television network decided to ride herd on the music stars, who typically turn out for the Grammys in provocative and often revealing fashions.

CBS inexplicably issued the guidelines last week, drawing hoots from critics. The memo touched off a lot of speculation over which stars, if any, would violated the guidelines and whether anyone will be banned from appearing in the audience as a result.

For the most part, at least the major stars were dressed appropriately, although some seemed to skirt the boundaries established by the networks.

The network called out stars to “be sure that buttocks and female breasts are adequately covered.”

“Please avoid exposing bare fleshy under curves of the buttocks and buttock crack. Bare sides or under curvature of the breasts is also problematic. Please avoid sheer see-through clothing that could possibly expose female breast nipples,” it added.

Rihanna apparently didn’t get the memo. Check out her photos and be sure to follow TheImproper on Twitter for the latest celebrity updates.