While the Patriots could make moves to keep both players, the Patriots may have to choose. If so, who should be their priority? To answer that question, we'll look at their production, versatility, uniqueness in the Patriots' system, durability and cost.
In 2013, Talib is tied for fifth among all defensive backs with four interceptions, and tied for 11th with 17 passes defended. More importantly, though, in the first half of the 2013 season, before he suffered a hip injury, he was able to almost single-handedly remove opposing teams' first option in the passing game, including Jimmy Graham against the New Orelans Saints and A.J. Green against the Atlanta Falcons.
Edelman's production in 2013 earned him the nickname Minitron from Patriots quarterback Tom Brady. That might be because, just as Megatron (the Detroit Lions' Calvin Johnson) is a weapon for Matthew Stafford, Edelman has become a safety blanket for Brady this season. He ranks fifth in the league with 89 catches for 914 yards and six touchdowns, all of which are at least double his previous career bests.
Talib essentially only plays cornerback. According to Football Outsiders, he's only played 16 special-teams snaps (4 percent) through Week 14 of 2013.
As Mike Reiss noted back in 2010, when Patriots head coach Bill Belichick called Edelman after drafting him, Belichick told Edelman that "We don't know what you're going to play, but we know you can play football."
As a rookie, Edelman doubled as both a wide receiver and a punt returner, replacing Wes Welker in that role. In his third season, the Patriots were forced to press him into duty as a cornerback. While he didn't become a Pro Bowler, he certainly held his own at the position as a rookie.
Neither player plays a unique role for the Patriots. The Patriots gave Danny Amendola a five-year deal worth about $30 million to be Wes Welker's replacement. Similarly, while Talib is the Patriots' best cornerback, they do have two young up-and-coming corners in Alfonzo Dennard and Logan Ryan.
Both Edelman and Talib have injury concerns. Edelman ended 2012 on injured reserve with a broken foot after missing several weeks earlier in the season with a hand injury. This season, though, he has thus far avoided the injury bug that has decimated the Patriots' offense; he is one of only four offensive skill players to play in every game for the Patriots this season (Tom Brady, LeGarrette Blount and James Develin are the others).
Talib has yet to complete a season in the NFL. Earlier this season, he missed three games with a hip injury; he has not notched an interception since his return. This is concerning, since hip injuries limited him late in 2012 as well.
According to OvertheCap.com, the going rate for top cornerbacks is about $8 million a year (Joe Haden, Cleveland Browns) to $11 million a year (Champ Bailey, Denver Broncos), with Darrelle Revis an outlier at $16 million a year.
The market for slot receivers is defined by Wes Welker and Danny Amendola, who each average $6 million a year.
This is a close decision, but in the end, the Patriots should make Julian Edelman their top priority, for three reasons. First, while his durability has been a concern, it has been more a series of freak injuries, similar to Amendola's, rather than a single chronic problem like Talib's.
Second, and more importantly, Edelman should cost significantly less to re-sign than Talib will, since the going rate for slot receivers is lower than it is for top corners.
The most important reason, though, is Edelman's productivity. He has shown that he can be a major contributor from the slot position, just as Wes Welker was when he was a Patriot. Letting Welker walk was tough, but—given his age—at least defensible. Letting Edelman walk would be much harder to defend.