The wide receiver had 36 catches for 380 yards and four touchdowns in four playoff games for the Baltimore Ravens, including six catches for 104 yards and a score against the San Francisco 49ers in Super Bowl XLVII.
After a surprising trade to San Francisco a week ago, Boldin will now attempt to help Kaepernick erase his Super Bowl demons by taking home this year's Lombardi Trophy.
Let's take a look at what Boldin can bring to the table in the 49ers offense.
Best hands in the league
I can't stress how important it is for the 49ers to field receivers that have great hands.
We learned in 2012 that Kaepernick is extremely accurate, but he throws so hard that some of San Francisco's receivers struggled to catch his passes.
Boldin had the lowest drop rate among qualified NFL receivers last season at 2.99 percent, per Pro Football Focus (subscription required).
In contrast, Randy Moss had a drop rate of 9.68 percent, and Delanie Walker had an abysmal 30 percent drop rate.
With a potentially healthy Mario Manningham (2.33 percent drop rate) and Boldin, Kaepernick shouldn't feel the need to force the ball to Crabtree in the big stages, like he attempted to do on San Francisco's final drive in Super Bowl XLVII.
Boldin isn't going to win many 40-yard dashes against other NFL receivers, but that's not all that goes into being a deep threat.
He is one of the best in the league at adjusting to the ball in the air and catching the ball away from his body. Combine that with savvy route-running, and you have a big-play receiver.
According to PFF, Boldin had 10 receptions for 20 yards or more last season (subscription required). He had the the third-highest catch rate on such passes among qualified receivers at 62.5 percent—much higher than Moss' 33.33 percent clip.
Much credit for Boldin's success should go to Joe Flacco. The Baltimore signal-caller tends to put more touch on the ball than Kaepernick, giving his receivers a chance to get it.
Also, Boldin's wide receiver partner in crime in Baltimore, Torrey Smith, is one of the fastest receivers in the league, which led to safeties cheating to his side of the field. This left Boldin with one-on-one matchups, and he often won them.
It's yet to be determined how often opposing cornerbacks will be left on an island with no safety help when covering Boldin on the 49ers. Crabtree is nowhere near the speed threat of Smith, but he's the best all-around receiver Boldin has played with since he was teammates with Larry Fitzgerald—Boldin was a three-time Pro Bowler as an Arizona Cardinal.
Then there's Vernon Davis, one of the fastest tight ends in NFL history, who always commands lots of attention from opposing safeties.
Although Boldin doesn't have the speed of a traditional deep threat, he could be San Francisco's most effective weapon 20 yards or more down the field next season if Kaepernick can learn to put more air under the ball and trust him to win one-on-one matchups.
In the video below, you'll see how versatile Boldin is:
He scored a touchdown against the 49ers on a slant-and-go and also had three other third-down-conversion catches—one on a back-shoulder route, another on an out route and another on a broken play.
Whereas Moss and Manningham don't make many plays over the middle against physical defensive backs, Boldin thrives in that role.
Boldin's physicality should also help San Francisco's running game. Much to my surprise, Boldin hasn't graded out well in PFF's run-blocking stats since 2008 (subscription required). Yet, he has the potential to be a far more effective blocker than Moss or Manningham.
He may not have the run-blocking skills to replace Walker, but he should hold his own when Kaepernick runs to the outside. And with Kaepernick's speed, that could be the difference between a short gain and a touchdown.
One of San Francisco's weaknesses entering the 2013 offseason was the lack of a quality No. 2 wide receiver.
With Boldin, that perceived weakness has the potential to be a strength.
Some fans might have wanted the 49ers to secure a younger option. But, the 49ers couldn't pass up acquiring a wide receiver who's been killing them for years for a measly sixth-round pick:
Anquan Boldin vs. #49ers through the years: 90 catches, 1,157 receiving yards, eight touchdowns. Yeah, they think he's worth a sixth rnder.— Matt Barrows (@mattbarrows) March 11, 2013
Paying $6 million for a 32-year-old supposedly past his prime is risky, but keep in mind that Boldin is coming off an incredible playoff performance and should help every aspect of the Niners offense.
Kaepernick was one of the best players in last year's playoffs without a quality No. 2 receiver. Imagine what he can do with Boldin?
There's no guarantee that Kaepernick will be as good or better than he was in 2012. But with Boldin and Crabtee attacking opponents from the outside, Davis from the middle and Frank Gore from the backfield, Kaepernick and the 49ers offense have a great chance at being more dynamic in 2013.