He's a former head coach with a vast defensive background and ties to Bill Parcells and Bill Belichick. He'll serve as—of all things—the senior offensive consultant for the reigning NFC champions.
Actually, the 49ers themselves are fascinating.
Due to the amazing assortment of talent general manager Trent Baalke inherited and has assembled over the last three years, the brilliant football minds of Jim Harbaugh and offensive coordinator Greg Roman have be afforded the luxury to tinker and experiment with a variety of schematic philosophies.
With everything from read-option concepts to the pistol to collegiate-style spread formations to traditional, jumbo-set power running, the current 49ers regime has been progressive enough to constantly confuse defenses while staying dedicated to the classic, fundamental aspects of running an offense that have withstood the test of time.
With dual-threat quarterback Colin Kaepernick, a player with gazelle-like speed in the open field and a cannon arm which he utilized en route to a 98.3 QB rating last year, and a menacing offensive line that consistently paved the way for three sound running backs, the possibilities are essentially endless.
After fielding one of the most efficient offenses in the NFL in 2012, for a club that's clearly not fond of complacency, these are three logical ways in which Mangini can help the 49ers.
Provide a perspective from a defensive mind
Mangini's first NFL job was with the Baltimore Ravens as the one of the team's offensive assistants, but after that, he coached the defensive side of the ball in New York with the Jets and in New England with the Patriots before head coaching stints with Jets and Cleveland Browns.
Aligning with the 49ers' way of creatively evolving vintage offensive principals, what's more simplistic yet imaginative than hiring a defensive mind to help improve the effectiveness of an offense?
According to Cam Inman of the San Jose-Mercury News, Mangini will be doing exactly that. He will be asked "to use his defensive insights in helping the 49ers offensive staff prepare for their NFC title defense."
More importantly, Mangini's defensive familiarity isn't limited to one alignment. In fact, he coached a hybrid defense in 2005 with the Patriots and utterly confused Tom Brady in a stunning 34-14 win over the heavily favored Patriots as the Browns' head coach in 2010.
With more teams implementing exotic, hard-to-decipher defensive fronts in today's NFL, Mangini's specific expertise should give way to invaluable insight on how to beat said defenses and how said defenses attempt to disrupt an offense.
Provide a perspective from a analyst's mind
For the last two years, Mangini has been an NFL analyst for ESPN.
Easily one of the most intuitive and thought-provoking X's and O's personalities at the Worldwide Leader, Mangini has had ample time to study the nuances of modern-day offensive attacks in the NFL from a broader perspective.
Prior to 2011, the overwhelming majority of his offseasons were extremely busy and team-centric.
There's a good chance his relatively less hectic schedule allowed him to learn a lot about the direction in which NFL offenses—and subsequently the defenses planned to stop them—are headed.
The knowledge obtained from Mangini's newly acquired point of view, along with his traditional coaching experience, likely enticed the 49ers en route to his hiring.
Typically, if a team sustains success in the NFL, its coordinators get snatched up to become head coaches elsewhere.
Luckily for the back-to-back division-winning 49ers, defensive coordinator Vic Fangio and offensive coordinator Greg Roman are still in San Francisco.
Fangio and Roman followed Harbaugh from Stanford in 2011, and it seems to be only a matter of time before they're both head-coaching candidates.
Mangini's hiring provides the 49ers coordinator insurance, especially on defense.
Jim Harbaugh's specialization is offense, therefore he probably would feel more comfortable if Roman departed than if Fangio was snagged by another team.
Mangini's unadulterated football genius seemed to outweigh the team-managing skills needed to thrive as a head coach, but, in theory, he would find himself in a tremendous situation solely overseeing a defense with a wealth of talent.
For an organization that's undoubtedly in win-now mode, the 49ers have a keen eye on the future with hopes of maintaining a perpetually triumphant team (remember, they made 11 selections in the 2013 draft).
The hiring of Eric Mangini makes that astute, forward-thinking philosophy blatantly obvious. San Francisco got an immensely experienced defensive coach who's had plenty of time to sharpen his football knowledge, and he provides wonderful coordinator insurance.
For a club that has recently exemplified "new-age NFL," the San Francisco 49ers made yet another intelligent decision.