The 49ers through free agency positioned themselves to be flexible with their first pick in the NFL draft next month.

They addressed their most pressing needs, signing cornerback Richard Sherman, replacing Carlos Hyde with Jerick McKinnon and making an upgrade along the interior of the offensive line with new center Weston Richburg. Most importantly, they have their quarterback situation solidified with Jimmy Garoppolo on his massive new five-year contract.

But, as always, sustaining long-term success is about finding core players to build around in the NFL draft. Here, we’ll take a look at three more mock drafts from this week and break down how each player would fit with San Francisco holding the No. 9 pick.

CBS Sports: Derwin James, S, Florida State

From Pete Prisco:

“They need a playmaker on the back end. With Eric Reid gone, James would step in and start.”

(Melina Vastola-USA TODAY Sports)

Safety is currently a position of strength but there are questions about the future, which would make James an intriguing addition. Yes, Reid is a free agent and unlikely to return after finishing second among 49ers defensive backs in snaps played in 2017. Moreover, Jimmie Ward and Jaquiski Tartt are both entering the final seasons of their rookie contracts.

Adding James could allow the 49ers to move on from either Ward or Tartt after the season while getting an upgrade in James at a financial discount. James’ rookie deal would be cheaper than new contracts for the incumbents. Tartt seems more likely to get a long-term pact done with San Francisco before the 2018 season begins because Ward has struggled with injuries throughout his four seasons.

Or, the 49ers could move Ward to the slot where he began his career and go with James, Tartt and Adrian Colbert as their three safeties. As the Seahawks proved over the last five years, you can never have too many good defensive backs. Tartt proved he could play free safety early last season and James looks like an ideal prospect to try replicating what Kam Chancellor was for Seattle.