Darnold is expected to visit the Broncos on Friday, per the report. Denver holds the fifth overall pick of the 2018 NFL Draft, which will be held on April 26-28 at AT&T Stadium in Arlington, Texas.
Although the Broncos signed Case Keenum to a two-year, $36 million deal last month, general manager John Elway has said that doesn't preclude the team from selecting any of the top-tier signal callers in the upcoming draft.
Darnold is viewed as the top overall prospect in the draft by NFLDraftScout.com senior analyst Rob Rang in his most recent Big Board. Rang lists UCLA quarterback Josh Rosen as second, followed by Penn State running back Saquon Barkley, Notre Dame offensive guard Quenton Nelson and North Carolina State defensive end Bradley Chubb.
The 20-year-old Darnold completed 303 of 480 passes for 4,143 yards with 26 touchdowns and 13 interceptions last season for the Trojans. He threw 31 touchdown passes as a redshirt freshman.
Keenum had his best season in 2017 after replacing injured Sam Bradford as the Minnesota Vikings' starting quarterback in the second game of the season. He completed 67.6 percent of his passes with 22 touchdowns and seven interceptions while going 11-3 in his 14 regular-season starts.
The Broncos also have a former first-round pick as a backup in Paxton Lynch, and they have quarterback Chad Kelly on the roster as well.
Denver limped to a 5-11 finish in 2017 with an offense that finished the season tied for 26th in the NFL in scoring. Trevor Siemian, Brock Osweiler and Lynch combined to complete just 58.7 percent of their passes for 3,668 yards with 19 touchdowns and 22 interceptions for a 73.0 passer rating.