With the vast majority of the top NFL free agents having signed with teams by now, we have a better idea of which areas certain teams are likely to improve in, as well as those in which they might decline.

Generally speaking, the 49ers have received very positive reviews for the developments of their offseason. They have addressed some of their biggest needs, and even managed to deal with Joe Staley's retirement on the fly while theoretically improving his spot on the offensive line in trading for Trent Williams. That said, it shouldn't necessarily come as a surprise that none of San Francisco's transactions were included among ESPN's Mike Clay's 25 biggest position upgrades of the NFL offseason. After all, when you have as stacked of a roster as the 49ers had last season, there isn't as much room to go up.

Just because the 49ers weren't included in Clay's rankings, however, doesn't mean they won't be significantly impacted by the top position upgrades in the league. In fact, there's a high likelihood San Francisco will be directly affected by each of what Clay has determined to be the three biggest upgrades in the NFL.

The single biggest position upgrade of the NFL offseason, according to Clay, is the one most certain to impact the 49ers of the top three. Why? Because the player providing the upgrade most recently played for San Francisco: defensive tackle DeForest Buckner.

 

"Colts general manager Chris Ballard said early in the offseason that the Colts' defensive scheme runs through the three-technique tackle," Clay wrote. "He put his money where his mouth is not long after, trading for Buckner. The 26-year-old was arguably the 49ers' best player during a 2019 season that saw the team advance to the Super Bowl. Buckner's 7 1/2 sacks tied for sixth, his 12 tackles for loss fifth and his 61 total tackles ninth among interior defensive linemen."

While Buckner will be a tremendous upgrade for the Colts over the incumbent Margus Hunt, he simultaneously leaves a giant void in the middle of the 49ers' dominant defensive line. San Francisco is counting on first-round draft pick Javon Kinlaw, as well as veteran D.J. Jones, to ensure that the 49ers don't suffer a corresponding downgrade.

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Coming in at No. 2 on Clay's list is the Tampa Bay Buccaneers replacing quarterback Jameis Winston with Tom Brady. Out of the top three, this one is the least likely to directly affect San Francisco.

While Brady actually produced an identically-poor quarterback rating (53.7) to Winston last season, the upgrade primarily is based on Brady's winning track record and his comparatively superior ability to limit turnovers. The Buccaneers made as much noise as any team during free agency, and Brady is a big reason why they have the third-best odds (+625) to come out of the NFC according to FOX Bet.

The 49ers (+460) currently are the favorites in the NFC, and while they won't face Tampa Bay during the regular season, there's certainly a decent chance the two teams could encounter each other in the playoffs. Not to mention, the Buccaneers appear likely to be one of the few teams capable of contending with San Francisco for the lone first-round bye in the conference. The 49ers had no trouble with Winston last season, but Brady potentially could be a different story.

And, finally, coming in as the third-biggest position upgrade on Clay's list is the Arizona Cardinals replacing Damiere Byrd with All-Pro receiver DeAndre Hopkins. San Francisco seems likely to feel the brunt of that development more than most.

"Cardinals GM Steve Keim and coach Kliff Kingsbury were not shy about their interest in adding an impact wide receiver during the offseason," Clay wrote. "It's fair to say their mission was accomplished when they fleeced Houston by landing one of the league's best pass-catchers in Hopkins in exchange for a package that included David Johnson. An absolute workhorse, Hopkins has averaged a target share of at least 30 percent while ranking no lower than 10th in targets, receptions, receiving yards and end zone targets each of the past three seasons."

 

Hopkins is on the shortlist of the very best receivers in the NFL, and now the 49ers must face him at least twice a season. The Texans received a laughable return in the trade as Arizona secured a true No. 1 target for reigning NFL Offensive Rookie of the Year Kyler Murray. It's quite possible that the Cardinals now are San Francisco's main competition in the NFC West, and Hopkins is a big part of that. Arizona pushed the 49ers to the brink in both of their matchups last year, and Hopkins should make them considerably scarier on offense.

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So, yeah, the 49ers have had a good offseason, but clearly, they're not the only ones.