THURSDAY, 12:47pm: The Vikings announced that their deal with Boone is now official.
WEDNESDAY ,3:18pm: Boone’s four-year deal is worth $26.8MM in total with $10MM guaranteed, Aaron Wilson of The Houston Chronicle tweets. Boone get $1.6MM in year one followed by three years at $6.6M with a $100K workout bonus.
10:50am: The Vikings will sign Alex Boone, a source tells Adam Schefter of ESPN.com (on Twitter). Exact terms of the deal are not yet known. 
After missing out on Kelechi Osemele this offseason, Boone was the Vikings’ Plan B. Boone does not offer the versatility that Osemele provides, but he is a solid consolation prize. On our list of free agent guards and centers for this offseason, Boone placed No. 5 behind Osemele, Alex Mack, Jeff Allen, and Richie Incognito.
According to the advanced metrics at Pro Football Focus (subscription required), Boone was the 38th best guard in the NFL last season with a strong 82.1 grade for pass blocking and a not-so-hot 44.9 grade for run blocking. Boone was on the field for 477 pass snaps and 308 run snaps last season with San Francisco.
It was reported that Boone could land a deal in the neighborhood of $8MM per year. With several suitors, including the Dolphins, the incumbent 49ers, and the Vikings, Boone was in prime position to cash in this month. Boone won’t be the anchor on any offensive lines, but he has made 59 starts over the last four seasons for the Niners and is a stalwart option at either guard position. PFR’s Luke Adams projected that a per-year salary in the $6-7MM range was within reach for Boone.
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