KUSA - If all goes well at the bargaining table for the Denver Broncos this week, Brock Osweiler will be the heir apparent to Peyton Manning.

There is the cold-hearted business and there are human relationships formed through working side-by-side for four years.

The Broncos signed Manning as a free agent in March, 2012. A month later, the Broncos grabbed insurance by drafting Osweiler in the second round. Manning announced his retirement Sunday. Osweiler is a free agent who will reach the tampering window Monday free to listen to other teams in need of a talented, 25-year-old quarterback.

"I will be forever grateful for the four seasons that Peyton and I shared together in Denver," Osweiler told 9NEWS via text. "Peyton's attention to detail, how he went about his preparation and his desire to win football games is what I will remember most. Peyton displays how to be the ultimate pro every single day and I am a better football player today because of my time spent with him.''

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Osweiler sat behind Manning for 3 1/2 seasons, finally getting his chance with seven games remaining in the 2015 regular season. Osweiler went 5-2 in those games but head coach Gary Kubiak went back to Manning during the Broncos' successful playoff run that culminated in a Super Bowl 50 victory.

The Broncos are trying to show they still love Osweiler by offering him a three-year contract that with incentives is worth more than $45 million. The guarantee of the deal, though, is always the most significant. The one team that may pose the most serious threat for Osweiler's services is the Houston Texans.

Houston is expected to contact Jimmy Sexton, Osweiler's agent, during the tampering period that begins at 11 a.m. Monday. Free agency officially opens at 2 p.m. Wednesday.