The Bucs and other NFL teams can begin negotiating contracts for free agents beginning at noon today. The new league year and signing period commences at 4 p.m. Wednesday.A big focus for the Bucs this offseason is locking up some of their own young stars. It began Friday with the signing of receiver Mike Evans to a five-year extension worth $82.5 million. There will be more between now and the start of the 2018 season.It's hard to know how active the Bucs will be in free agency. They have big needs on the defensive line and at cornerback, guard, running back and safety, so the shopping list begins there.The goal is to fill as many needs as possible prior to the draft so the Bucs are not held hostage to any position and can attempt to select the best player available. This happened last year when tight end O.J. Howard fell to them with the 19th overall pick.The Bucs did not have a huge need at the tight end position, but they felt comfortable taking the best player.In addition to evaluating other free agents, the Bucs can continue to re-sign their own. They have 15 players prepared to hit the market.Among those who saw significant time as starters are cornerback Brent Grimes, left guard Kevin Pamphile, cornerback Robert McClain, defensive tackle Clinton McDonald and kicker Patrick Murray. There also are several restricted free agents the Bucs would like to lock up, such as tight end Cameron Brate and receiver Adam Humphries.The Bucs own the exclusive rights to running back Peyton Barber, who is expected to return to the club as the team's leading rusher.Both coach Dirk Koetter and general manager Jason Licht have said they want Grimes to return, but he is definitely going to talk with other teams to determine his value.Who are the marquee players in free agency from other teams that the Bucs will at least consider? Several are with the New England Patriots. Running back Dion Lewis rushed for 896 yards and averaged five yards per carry with six touchdowns. He added three more as a receiver.Cornerback Malcolm Butler, who was inexplicably benched for the Super Bowl, has a good resume. Left tackle Nate Solder may re-sign with the Patriots but the Houston Texans reportedly have an interest.The best guard available is Carolina's Andrew Norwell, but reports say he could earn as much as $12-million per year.It's going to be a wild three days, with news of agreements coming fast and furious by 4 p.m. Wednesday. The Bucs have $71.158 million under the salary cap, which is the fourth-most in the NFL, giving them lots of resources to acquire players.