The Tampa Bay Buccaneers will host Marcus Mariota for a visit on Monday, according to Rick Stroud. Roy Cummings describes it as "just a visit" with a private workout set to happen in April. Mariota's visit comes on the heels of yesterday's Oregon Pro Day, where he performed basically as expected in a controlled environment.
Jameis Winston visited the Bucs last week, and the Bucs promoted that visit pretty heavily. They posted an interview with Winston on their website, and covered his visit with several articles. Some took that to be a sign that he's the pick, but I expect the team to do the same with Mariota once he visits. We'll get the chance to compare that reaction on Monday.
Regardless, Mariota's visit will be important to test his understanding of a pro-style offense, and his ability to transition quickly. While there apparently won't be any on-field workouts, they can still quiz and interrogate him, and get to know him as a person, of course.