The 11-year veteran was the 49ers' most productive receiver in 2013, catching 85 passes for 1,179 yards and seven touchdowns.
The 33-year-old was worth every penny of his $6 million 2013 salary. But now he's entering free agency.
Though the 49ers would love to have Boldin back, they can afford to lose him. Here's why.
Michael Crabtree Returning to Form
It's easy to forget how good Crabtree was a year ago.
In the last eight games of the 2012-13 season (playoffs included), Crabtree had 55 catches for 823 yards and seven touchdowns. He was San Francisco's only consistent performer at the receiver position, and he still put up big numbers with Colin Kaepernick down the stretch.
Crabtree tore his Achilles in May, and he missed the first 11 games of San Francisco's 2013 campaign. Though he showed flashes of his talent after his return, he wasn't quite the same.
With a healthy offseason to procure his craft, Crabtree could return to being a high-end No. 1 receiver. If so, the 49ers won't need Boldin, though they'll still need to find a capable second option through free agency or the draft.
49ers Draft Options
The long-term future of San Francisco's wide receiver corps is up in the air, even if Boldin is re-signed.
Crabtree is only under contract for one more season. No other wide receiver currently under contract had more than three catches in the 2013 regular season.
It's more than likely the 49ers will spend at least one of their five picks in the first three rounds of the NFL draft on a wide receiver. If they don't re-sign Boldin, they will almost assuredly use their first pick on a wide receiver—possibly even trading up for one.
Clemson's Sammy Watkins, Texas A&M's Mike Evans, USC's Marqise Lee and Florida State's Kelvin Benjamin are all destined to go in the first round of the draft. Any of the four could be San Francisco's No. 2 wide receiver in 2014.
Of course there's a chance the 49ers draft the next A.J. Jenkins. But sometimes that's a risk a team has to take. If the 49ers guess right, they could end up with the perfect complement to Crabtree and Vernon Davis. And if that complement is drafted, he'll be far cheaper than Boldin and could develop into a star receiver down the road.
Improving Other Positions and Extending Stars with Freed-Up Money
By letting Boldin go, the 49ers would be running the risk of a less prolific wide receivers corps any way you slice it. However, with $6 million to spend on other positions, they would have a better chance to improve other areas and/or sign their top players to extensions.
Crabtree, Kaepernick and Aldon Smith will all be entering their contract year in 2014. If the 49ers higher-ups feel the best way to keep any or all of those three long term is to let Boldin walk and extend them this offseason, then that's a decision worth making.
Suppose the 49ers do find a cheaper No. 2 receiver through the draft or free agency. The money saved could also help them land reinforcements in the area they need them most—the secondary.
The Niners could go after a big-name cornerback, such as Brent Grimes (second in Pro Football Focus' 2013 cornerback rankings) or Vontae Davis (third in PFF's CB rankings, subscription required). Either one would be an upgrade over Carlos Rogers, who could get cut, or free-agent-to-be Tarell Brown.
Maybe the Niners decide re-signing Donte Whitner is more important than keeping Boldin. Or if they lose Whitner and/or Boldin, they go after Jairus Byrd. The Buffalo safety has placed in the top 10 of Pro Football Focus' safety rankings in each the last three seasons (subscription required).
To be sure, letting Boldin walk will give the 49ers more options elsewhere.
I'm not suggesting the 49ers should let Boldin go under all circumstances. If he wants to sign a cheap, team-friendly deal, the Niners should pounce on that in a heartbeat.
As Pro Football Talk's Mike Florio noted, Boldin hinted that he wants to return to the 49ers for a second year with this tweet:
That being said, Florio wrote that Boldin refused a $2 million reduction during last year's offseason. That likely played a huge role in the Baltimore Ravens trading him to the 49ers for just a sixth-round pick.
If anything, Boldin was more impressive in 2013 than 2012, so I'm not expecting the 49ers to get him for a bargain.
It all comes down to Trent Baalke's plan. If, after crunching the numbers, he believes Boldin fits into the team's short-term future, the wide receiver will likely be back in red and gold in 2014.
If the numbers don't quite add up, Baalke should let him loose.