The Patriots' biggest concern last year was the loss of Tom Brady's favorite target, Wes Welker. If they want to avoid another year of facing the exact same questions about losing Brady's most reliable receiver, they cannot afford to let Edelman leave.

Their recent undervaluing of Welker may serve as a red flag to their perception of the slot receiver position, but there are plenty of reasons they could hold Edelman in higher regard. For starters, the relationship between Welker and head coach Bill Belichick had become strained by the end of Welker's time in New England, but the next time Belichick shows any ill will toward Edelman will be the first time.

There's also far more tread on the tires of a 27-year-old Edelman than there were on a 31-year-old Welker. The elder of the two had handled the ball 1,211 times prior to this year, where the younger one has done so just 321 times.

The Patriots learned first-hand this year how important it is for Brady to have trust in who he's throwing to. By the end of the season, Edelman was the only player that truly fit that description. He led the team in targets in nine of their 18 total games, seven of their last eight games, and all five games after Rob Gronkowski went down with a season-ending knee injury.

In year's past, Welker was the one that bore the burden of the offense as the wheels fell off the bus. This year, Brady set his GPS in Edelman's direction and hardly ever veered off his path.

"I mean, he was one guy that was so consistent and dependable for us. I'm just proud of him because of his mental toughness and maturity and his work ethic," Brady said Monday of Edelman on WEEI, adding, "I love him, he’s one of my best pals, I spent a lot of time with him. I'm just proud of him for everything that he's accomplished. He deserves the best."

Edelman went out of his way to improve his chemistry with Brady, and earned "pal" status by moving out to Los Angeles, Calif. to work out with Brady in the offseason. It's safe to say the work paid off.

His value is enhanced further by his ability on punt returns. He averages 12.3 yards per punt return, the best among active players and seventh-best all-time. The 2013 season was his first year without a punt return touchdown since 2009, having logged one each year from 2010-2012.

Belichick may be hesitant to spend big on another free agent after dishing out a five-year, $28.5 million contract to Danny Amendola, who was supposed to be the heir to the slot for Welker. Amendola and Edelman are similar players — so similar that the two earned the nickname "Edelmandola." They are both better suited in the slot, although Edelman lined up on the outside about half the time in 2013. Amendola's contract is only guaranteed through next season, so the Patriots could choose to part ways at that point, if things still haven't worked out.

If the Patriots need to justify spending a few extra dollars on Edelman, they can look at the bargain-basement rate they spent on him this past season. He made $1.015 million for his 105 catches ($9,666.67 per catch), 1,056 yards ($961.17 per yard) and six touchdowns ($169,166.67 per touchdown). For context, the Houston Texans spent $14.675 million on Andre Johnson, who put up 109 catches ($134,633.03 per catch), 1,407 yards ($10,429.99 per yard) and five touchdowns ($2.935 million per touchdown).

Those numbers don't tell the whole story of these two receivers, but they are an accurate summary of Edelman's value to the team in 2013, and beyond. He is obviously not the physically gifted athlete that Johnson is. He's not going to command double-teams and put stress on a defense vertically, and he doesn't have basketball-like leaping ability, but he has something that's proven more important than any of those physical gifts: chemistry with Brady.

He was the best value on the Patriots — and possibly even the NFL — in 2013, and is the most trusted target at Brady's disposal not named Gronkowski. Those two factors alone make him the most important free-agent on the Patriots' docket this year.

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