The Bears are taking their time to find a WR coach who can work with Brandon Marshall. (US Presswire)

When Chicago Bears head coach Marc Trestman formally introduced his new staff on Thursday one spot on the coaching roster remained conspicuously empty.

Trestman, who earned a reputation as an offensive guru for his work with Jerry Rice in San Francisco, has yet to name an assistant to coach the team’s wide receivers.

"We have one more coach to hire and we're going through the process,” Trestman told the Chicago Tribune. “I think we are close to a resolution in terms of hiring a wide receivers coach.”

The Bears are fairly thin at receiver beyond Brandon Marshall. In 2012, the Pro Bowl wideout set franchise-records with 118 receptions and 1,058 receiving yards. Chicago’s next three receivers in terms of production -- Earl Bennett, Alshon Jeffery and Devin Hester -- combined for 76 catches and 984 yards.

The Bears also learned that Johnny Knox is likely to retire after missing all of last season with a serious back injury.

It will be critical for the WR coach to establish a strong rapport with Marshall. Besides helping Marshall put up record numbers, former Bears WR coach Darryl Drake also found ways to keep Marshall under control in practices and meetings, according to the Tribune. Marshall’s off-field reputation played a role in his departure from Miami. It might be why Trestman has been so deliberate with the hiring.

Only two wide receivers have received mid to high first-round grades in CBSSports.com’s latest projections. The Bears may be reluctant to draft a receiver in the early rounds again after selecting Jeffery in the second round last year. A deep free-agent class at wideout includes Victor Cruz (Giants), Mike Wallace (Steelers), Wes Welker (Patriots), Dwayne Bowe (Chiefs) and Greg Jennings (Packers).

Hester is set to become a free agent after the 2013 season, and Bennett and Jeffery are under contract through 2016.

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