Colin Kaepernick trade to Broncos being held up by $4.9 million

San Franciscoand Denverhave the parameters of an agreement in principle on a trade for quarterbackColin Kaepernick, sources said.

But before a deal is completed, the 49ers, Broncos and Kaepernick have to agree on who will pay the quarterback's $11.9 million guaranteed salary for this upcoming season, according to a source.

The Broncos are willing to pay $7 million, a source confirmed to ESPN. But Denver and Kaepernick would like the San Francisco to pay the remaining $4.9 million; the 49ers have been unwilling, according to a source, believing they should not have to pay for a player they'd like to keep on their roster. Kaepernick has also been unwilling to forfeit the $4.9 million to make the deal work, according to a source.

A high-level source says "it would take two seconds" for the teams to finalize the proposed deal. The compensation in the trade is a nonissue, per sources familiar with deal. It will be a midround pick and sources from both teams said that will not be any holdup and they can "finalize it with one phone call."

Adding to the pressure, the 49ers' offseason voluntary workout program starts Monday, and Kaepernick has a $400,000 offseason workout bonus for 90 percent attendance.

Kaepernick and Broncos executive vice president of football operations/general manager John Elway have met twice, as the San Francisco Chronicle previously reported. Kaepernick and Denver have made progress on the other years in the quarterback's contract, which runs through 2020, leaving the 2016 season as the only obstacle, according to a source.

Denver, which lost Peyton Manning to retirement and Brock Osweiler to the Houston Texans in free agency, has long been linked to Kaepernick and has reportedly envisioned him competing with the recently acquired Mark Sanchez.