The Vikings lost three quarterbacks in free agency, but they've already added two new ones to their roster. 

On Wednesday, a day after the Vikings agreed to sign Kirk Cousins to a three-year fully-guaranteed deal, the Vikings engineered a trade for Broncos quarterback Trevor Siemian, according to NFL Network's Ian Rapoport. It's not yet known what the exact terms of the trade are, as Rapoport reported that the trade is still being finalized. But ESPN's Adam Schefter reported that the Broncos are getting a 2019 draft pick while the Vikings get Siemian and a late-round pick in this year's draft.

Minnesota of all teams understands just how valuable a backup quarterback can be. This past season, the Vikings entered the season with Sam Bradford as their starter, but lost him early on to a knee injury. In stepped Keenum, who wound up leading the Vikings all the way to the NFC Championship Game. Without Keenum, the Vikings would've been sunk. Instead, they nearly became the first team in NFL history to host a Super Bowl in their own stadium.

Keenum, along with Bradford and Teddy Bridgewater, all hit free agency this week. The entire trio left Minnesota, with Keenum winding up in Denver, where he'll replace Siemian as the Broncos' starting quarterback. With Siemian out of the picture, look for 2016 first-round pick Paxton Lynch to compete with Chad Kelly for the Broncos' backup job. The Broncos also might add another quarterback through the draft considering they hold the fifth-overall pick. 

Meanwhile, the Vikings chose to pursue Cousins instead of retaining Keenum. They won the Cousins sweepstakes, but they still needed a backup quarterback. That role now belongs to Siemian, who brings starting experience to Minnesota. Siemian's started 24 games in his three-year career, posting a 13-11 record. In his career, he's completed 59.3 percent of his passes, averaged 6.8 yards per attempt, thrown 30 touchdowns and 24 interceptions, and accumulated a 79.9 passer rating. Those aren't starting-caliber numbers by the NFL's standards, but the Vikings don't want him to start unless something bad happens to Cousins, in which case they'll need him to keep them afloat.

So, as of Wednesday night, the Vikings' quarterback depth chart looks like this:

  1. Kirk Cousins
  2. Trevor Siemian
  3. Kyle Sloter 

While the Broncos' quarterback depth chart looks like this:

  1. Case Keenum
  2. Paxton Lynch
  3. Chad Kelly

Teams still searching for backup quarterbacks are now left to pick from a group that includes AJ McCarron, Matt Moore, Chad Henne, Geno Smith, and Brock Osweiler. Earlier on Wednesday, the Bears signed Chase Daniel. Shortly after news of the Siemian trade broke, the Saints signed Tom Savage.