Exactly one year ago from this coming Sunday, news broke that the Vikings had traded for wide receiver Mike Wallace. The hope was that Wallace would inject life into the Vikings' passing game as a deep threat. That never materialized.

So after a lackluster season in which Wallace caught just 39 passes, the Vikings cut him. They saved $11.5 million on the salary cap in the process, money they are starting to invest in free agents such as guard Alex Boone of the 49ers. That said, the idea that Wallace had a disappointing season isn't simple. Instead, it's rooted in multiple issues:

• Teddy Bridgewater is a very accurate short passer. But if Wallace was signed ostensibly to stretch the field, he was paired with a QB for whom that is not — at least not yet — a strong suit.

In his career, Bridgewater has attempted 35 passes that traveled more than 30 yards beyond the line of scrimmage. He's completed four of them. It's hard to make plays if you can't get the ball. It's a part of Bridgewater's game that will either need to evolve or need to be masked.

• Not all of that is on Bridgewater, of course. You could argue that offensive line play was a larger culprit in preventing the Vikings from attempting and completing deep passes last season. Bridgewater topped all NFL quarterbacks in the percentage of dropbacks on which he faced pressure.

You can't throw deep if you don't have time. This is one of the 823 reasons the Vikings must improve their offensive line dramatically this offseason. Signing Boone is a start, but more work remains.

Wallace and Teddy Bridgewater didn’t connect very often on the football field, particularly on deep passes, which was Wallace’s specialty.

• Wallace's role and the Vikings' offensive philosophy shifted during the season. Wallace, through four games, had 20 catches. He was on pace for 80 grabs and more than 900 yards.

Two things happened around the same time after that: The Vikings' offense became more conservative and focused on Adrian Peterson while Stefon Diggs emerged as a top Bridgewater target after being inactive for the first three games.

In the next seven games, Wallace had eight catches combined, for fewer than 100 yards. The Vikings won six of those games, so the method was clearly working. But Wallace's numbers clearly suffered.

• Wide receivers are at their peak production when they are around 26 or 27 years old, according to Pro Football Focus. It's possible that Wallace — who averaged more than 1,000 yards per season in his five years between the ages of 24 and 28 — started a period of decline last year at age 29.

A deep threat who loses even half a step suddenly isn't as threatening (or potentially open) as he once was.

The complete answer as to why Wallace and the Vikings weren't the right fit was probably a combination of a lot or even all of these things. What we do know is that Wallace and the Vikings weren't a good match in 2015, and it was probably best for both sides that they moved on from each other.