With free agency and the NFL draft on the horizon, Chip Kelly's tenure as 49ers head coach is rapidly approaching take off.
Changes will be made to the roster and scheme, and San Francisco will begin to form a new identity.
But what will Kelly's second turn as an NFL head coach look like? One of his former players weighed in.
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SIGN UP HERE "I'm not sure (how he'll work out)," Super Bowl winning guard Evan Mathis told Bill Lekas and Takeo Spikes on SiriusXM NFL Radio Sunday. "A lot of factors go into that.
[RELATED: Ex-49er questions if team can endure loss of Harbaugh]
"I think Chip Kelly, he's a good coach," he added. "And I think he'll have better success if he's not trying to wear too many hats."
Mathis, a 12-year vet and first-team All-Pro, played under Kelly with the Eagles from 2013-14.
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Months of contract tension eventually led to the outright release of a then-33-year-old Mathis. This is when Kelly had more of a say in personnel, correlating with Mathis' reference about wearing "too many hats."
The Pro Bowler insisted on SiriusXM NFL Radio that Kelly will succeed if he narrows his focus to coaching.
Kelly at the time was up front about where Mathis stood with the team, saying, "We have never had an offer for Evan so there's nothing to take.
"Evan's been available to trade for two years now and we've never had an offer for him," Kelly said, according to Jimmy Kempski of the Philly Voice. "And that's through their agent and him. They've asked us if he can renegotiate a contract and see what he can get and we've obliged him with that, but we've never had an offer on him."
With his release on June 11, 2015, Mathis joined several distinguished players to be let go or moved from Kelly's Eagles, including LeSean McCoy, Brandon Boykin, Nick Foles and DeSean Jackson.
Leading receiver Jeremy Maclin also walked in free agency.
The 49ers named Kelly head coach on Jan. 14, 2016. He became the organization’s seventh head coach of the past 15 years.