Signing Carlson worth the risk to Cards

One thing we knew for certain this offseason was that the Arizona Cardinals needed help at tight end. Some relief came Friday when the team announced it signed former Minnesota Vikings tight end John Carlson to a two-year contract. Terms of the deal were not immediately available.

Carlson's health has been the primary concern surrounding the 6-foot-5, 248-pound tight end, especially during the past few seasons. He suffered the third known concussion of his NFL career in early December and was placed on IR two weeks later. According to the Minneapolis Star-Tribune, Carlson contemplated retirement after his last concussion and before he was released after his second season with the Vikings.

Arizona has been here before. The Cardinals drafted Ryan Swope last season out of Texas A&M despite knowing he had a history of concussions. An injury during organized team activities and minicamp last spring eventually forced Swope to retire before playing a single snap in the NFL.

The reason Arizona signed Carlson was the same reason it drafted Swope. The reward is greater than the risk. If Carlson regains his form as one of the top tight ends in the NFL, which he was during his first two seasons in the league with Seattle, the Cardinals could have three all-around threats at tight end with Carlson joining Rob Housler and restricted free agent Jake Ballard.

Carlson had 344 yards and one touchdown on 32 catches in 13 games last season, not quite his career-highs of 627 yards on 55 catches and five touchdowns in all 16 games as a rookie in 2008 but still solid numbers.

If Carlson suffers another head injury, it's likely his career will be over. That's the risk -- which is much greater for Carlson than the Cardinals -- but Arizona can benefit from Carlson even as a third tight end, filling Ballard's role from 2013.

Arizona won't stop looking for tight ends. The Cards will continue combing through the waiver wire, looking through free agency and scouring the draft boards for another tight end in case Carlson doesn't work out.

But for now, the reward he can provide is a lot greater than the risk Arizona is taking.