Casillas was not with the team at the game.
The 27-year-old is listed as the Bucs starter at strong-side linebacker on the team's depth chart.
Casillas, who was signed by the Saints in 2009 after going undrafted out of Wisconsin, is entering his fifth season in the NFL.
In 2013, Casillas played 12 games for Tampa Bay, making four starts and registering 33 tackles.
- Molly Geary