Denver has waived 2013 seventh-rounder Zac Dysert, who had served as their third-string quarterback last season and this summer.
That leaves only Peyton Manning and Brock Osweiler at the position.
Painter spent most of the season on the Broncos' practice squad, but was promoted late in the year to prevent San Francisco from poaching him.
In a confirmation of their newfound defensive line depth, the Broncos have released veteran tackle Kevin Vickerson.
Big Vick totaled 108 tackles, five sacks, one interception, seven passes defensed, and two forced fumbles in 47 games (41 starts) over four seasons with the team.
After Brandon McManus's scattershot performance on Thursday, the Broncos are working out more young kickers on Saturday.
Is Kyle Orton the new Brett Favre? Perhaps, at least in the worst way.
Six weeks after having been cut by Dallas under the guise of retirement, Orton has reportedly agreed to a two-year deal with Buffalo.
It's widely being reported as a one-year contract, but Tim Graham says Orton holds a hefty option for a second year.
According to the Denver Post, the Broncos trimmed their active roster to 66 players on Friday, ahead of Saturday's deadline to reach the 53-man limit.
Seven players were reportedly waived or cut: defensive tackle Sione Fua, tight ends Cameron Morrah and Jameson Konz, corners Jordan Sullen and Jerome Murphy, tackle Ryan Miller, and linebacker L.J. Fort.
Defensive end Kenny Anunike (elbow) will apparently be stashed on IR, while kicker Matt Prater is headed to the reserve/suspended list.
The Broncos acquired kicker Brandon McManus (6-3, 201) from the Giants in exchange for a conditional 2015 seventh-rounder.
According to Mike Klis, Denver will only owe New Jersey the pick if McManus remains the Broncos' starting placekicker beyond Matt Prater's four-game suspension.
The Giants were set to waive McManus after naming Josh Brown their starting kicker, but apparently got wind that their NFCE rival Eagles were interested in the youngster.
The Broncos got down to Tuesday's 75-man roster limit when they placed wideout Jordan Norwood on IR and waived defensive tackle Cody Larsen.
Rosters must be pared to the 53-man limit by 4pm ET on Saturday.
Jeff Legwold and Mike Klis have each reported that Denver will be watching the waiver wire for kickers to step in during Matt Prater's four-game suspension.
Far be it from us to provide scouting reports on these guys, but here's what we know:
The Broncos cut 11 players on Sunday night, including tackle Winston Justice and running backs Brennan Clay and Jerodis Williams.
Along with the two backs, wideouts Greg Wilson and Greg Hardin, LB Jerrell Harris, DT Will Pericak, S Charles Mitchell, and QB Bryn Renner were waived.
LB Jamar Chaney and DE Chase Vaughn were let go with injuries.