We're officially one week into free agency, and the 49ers have [made some significant changes](https://www.si.com/nfl/49ers/onsi/news/ranking-49ers-offseason-moves-so-far-best-worst) to their starting lineup. In fact, they'll have at least four new starters -- two on offense, and two on defense.
Let's break down the lineups.
OFFENSE
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**X Wide Receiver:** Mike Evans
**Z Wide Receiver:** Ricky Pearsall
**Left Tackle:** Trent Williams
**Left Guard:** Brett Toth
**Center:** Jake Brendel
**Right Guard:** Dominick Puni
**Right Tackle:** Colton McKivitz
**Quarterback:** Brock Purdy
**Running Back:** Christian McCaffrey
**Fullback:** Kyle Juszczyk
Mike Evans is the big addition to the offense. He replaced Jauan Jennings, who replaced Brandon Aiyuk as the starting X receiver. Evans will be 33 this year, and he's coming off the worst season of his career, so you have to wonder how much his body has left.
As opposed to Aiyuk, who will be 28 next season and has had two years to recover from his knee injury. The 49ers haven't released him yet because they're hoping to trade him to Washington for a seventh-round pick. Had they traded him two years ago, they might have been able to get a first-round pick for him. Now, they most likely will get nothing for him. They'd better hope Evans stays healthy and Aiyuk doesn't play well for Washington when they inevitably release him.
The other new addition to the starting lineup is Brett Toth, the soon-to-be 30-year-old guard who has started a whopping six games in his career. But, he's cheap, and he's old -- two things Kyle Shanahan loves in his players.
DEFENSE
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**Left Defensive End:** Mykel Williams
**Left Defensive Tackle:** Alfred Collins
**Right Defensive Tackle:** Osa Odighizuwa
**Right Defensive End:** Nick Bosa
**Weakside Linebacker:** Dre Greenlaw
**Middle Linebacker:** Fred Warner
**Left Cornerback:** Deommodore Lenoir
**Strong Safety:** Malik Mustapha
**Free Safety:** Ji'Ayir Brown
**Right Cornerback:** Renardo Green
**Nickelback:** Upton Stout
Osa Odighizuwa will be a massive upgrade over Kalia Davis and Jordan Elliott -- the two starting defensive tackles from last season. They were run-stuffers who provided zero pass rush. Odighizuwa is a pass-rush specialist from the interior.
Bryce Huff retired, so the 49ers have to find a new designated edge-rusher for passing downs. Or, they could trade for Maxx Crosby and make themselves legitimate Super Bowl contenders. More likely, they'll sign Joey Bosa or draft an edge rusher and come up slightly short in their quest for a sixth Lombardi Trophy once again.
Dre Greenlaw's return to the team is a big boost as long as he's healthy. He hasn't played much the past two seasons, but he's more than two years removed from his torn Achilles, so maybe his body has finally recovered.
At free safety, don't be surprised if second-year player Marques Sigle takes Brown's job during training camp. Sigle is much faster than Brown -- he just needs to work on finishing plays.
SPECIALISTS
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**Punter:** Corliss Waitman
**Kicker:** Eddy Pineiro
**Long Snapper:** Jon Weeks
**Punt Returner:** Jacob Cowing
**Kick Returner:** Isaac Guerendo
Waitman has a big leg, but he's inconsistent -- he was top 5 in the league in hang time last season but 27th in the league in yards per punt, which indicates that he shanks a fair amount of his attempts.
The 49ers used to have an elite return man in Skyy Moore -- now they have Cowing and Guerendo. Expect the 49ers to draft Moore's replacement with one of their fourth-round draft picks.