NFL Network's Ian Rapoport confirmed the report Saturday.
Kelly has had limited success at the NFL level and was fired by the Philadelphia Eagles after last season. He signed a four-year, $24 million contract with the Niners, though they entered Week 17 just 2-13 on the season.
His detractors point to a lack of creativity in play-calling and an offensive system that, when it isn't executed properly, puts a lot of pressure on the defense. And according to Jason La Canfora of CBSSports.com, "Kelly's offense continues to be ridiculed by his peers in the NFL."
Many believe that Kelly's no-huddle, fast-paced, zone-read offensive scheme fits the college game better. In the NFL, the quality of the players and the sophistication of most defensive schemes have rendered Kelly's approach less effective, and he hasn't consistently made the adjustments necessary to adapt.
Kelly's supporters, on the other hand, can point to the fact that in his four seasons as an NFL head coach, he's never had a quarterback who is well-suited to his scheme. He also led the Eagles to consecutive 10-6 seasons in his first two years at the helm and, in San Francisco, took over a team that was already in rebuilding mode.
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