From the time K’Waun Williams joined the 49ers in 2017 as an under-the-radar signing, San Francisco believed it had one of the top nickel backs in the NFL.
Williams appeared in 71 games, including postseason, in his five years with the club. He played exclusively on downs in which the opposition lined up with three or more wide receivers.
Williams, who turns 31 in July, agreed on a two-year, $7 million contract with the Denver Broncos on Tuesday, Mike Kaye of Pro Football Network reported Tuesday, citing league source.
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Now, the 49ers must come up with a new plan for facing Cooper Kupp and any of the other top slot receivers on their schedule.
The top options on the 49ers' roster to play nickel back could be Deommodore Lenoir and Emmanuel Moseley.
Lenoir, a fifth-round draft pick from Oregon, had a strong training camp as a rookie. He started the first two games of the 2021 season at cornerback.
He also saw time at nickel back before a couple of late-game mistakes played a role in the Green Bay Packers’ last-second victory in Week 3.
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Or, the 49ers could put more on the plate of Moseley as they move on without Williams.
The 49ers’ signing of free-agent cornerback Charvarius Ward last week could enable the team to move presumptive starter Moseley inside on passing downs and replace him in those situations with Ambry Thomas.
The 49ers have long-considered free safety Jimmie Ward as one of their top cover men in the defensive backfield, and he has experience at nickel back. However, the club prefers to keep him as the last line of defense in passing situations.
The 49ers have nine scheduled draft picks in the 2022 NFL Draft. They are likely to use multiple picks to accumulate depth for the defensive backfield.
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The biggest matchup the 49ers’ secondary faces will come from the Super Bowl-champion Los Angeles Rams. Kupp led the NFL last season in receptions (145), yards receiving (1,947) and touchdowns (16).
In three games against the 49ers, Kupp caught 29 of the 34 passes that quarterback Matthew Stafford pass intended for him, totaling 382 yards and three touchdowns.
Williams opted not to play in the 49ers' final regular-season game against the Rams because he felt he was not prepared after spending time on the reserve/COVID-19 list that week. The 49ers won that game, 27-24, in overtime to earn a spot in the NFC playoffs.