Fantasy Upside
There's a reason Tampa Bay selected Jameis Winston as the first overall pick in this year's draft. He has a ton of talent, and will be the team's starting quarterback from day 1. Winston is coming into a solid set up. He gets to throw to tall receivers like Mike Evans, Vincent Jackson and tight end Austin Seferian-Jenkins. Tampa also lacks a solid run game, which means more pass attempts should be coming. Winston will also be working with offensive coordinator Dirk Koetter. Koetter comes from Atlanta, where he helped Matt Ryan have a great amount of success. Ryan threw for more than 4,500 yards in each of his three seasons with Koetter. He also led David Garrard to his four most productive seasons as an OC in Jacksonville.
Fantasy Downside
Winston's biggest downfall is his knack for throwing interceptions and turning the ball over. It's something he dealt with at Florida State, and it will likely be something he deals with as he adjusts to the speed of the NFL in his first season. Also, while we've seen rookie quarterbacks have success in the recent past, we've seen plenty of them struggle as well. It's incredibly difficult to predict how quickly a rookie will adapt in his first year.
Bottom Line
You don't want to have a rookie quarterback as your main option. Winston could be worth a late round selection (if you like rostering two quarterbacks) as he's a promising prospect, but he's not even close to QB1 range at this point.