Patrick Mahomes is making the Kansas City Chiefs' brain trust look like geniuses for trading away veteran Alex Smith in the offseason and turning the offense over to the second-year quarterback.

The Chiefs are off to a blazing 3-0 start under Mahomes and are averaging a league-high 39.3 points as they prepare to visit the Denver Broncos in a prime-time matchup on Monday night.

Mahomes already has made history before Kansas City hits the quarter-pole of the 16-game campaign, becoming the first quarterback to throw for 13 touchdowns in the first three games of a season. Mahomes, who also has not been intercepted, eclipsed the previous record held by Peyton Manning.

"It speaks to the guys that we have," Mahomes said after throwing for 314 yards and three scores in last weekend's 38-27 win over the San Francisco 49ers. "We're really deep at every single position. Knowing that I have those weapons whenever someone has to get a break -- we say if you're tired get a break, because I know that I can trust the next guy coming in that he'll make a play."

Mahomes' early success comes as no surprise to the best defensive player on the Broncos. Linebacker Von Miller got a close-up view of Mahomes in the 2017 regular-season finale in Denver.

Making his first career start, Mahomes finished 22 of 35 for 284 yards and an interception. Mahomes left the game in favor of third-string quarterback Tyler Bray but re-entered the contest for his team's final drive, leading the Chiefs to a game-winning field goal.

"From that game you could tell he's going to be the future," said Miller, who is tied for the NFL lead with 4.0 sacks. "He's a great quarterback, he can make all the throws, quick, athletic, young. He's got everything you want."

Mahomes has completed touchdown passes to nine different receivers. Explosive wideout Tyreek Hill already has eight catches of at least 20 yards to go with three touchdowns while tight end Travis Kelce boosted his team-high total to 16 catches with back-to-back 100-yard games.

Denver head coach Vance Joseph noted the difficulty of preparing for the Chiefs, who have another deep threat in Sammy Watkins and a top-flight running back in Kareem Hunt, the NFL's leading rusher a year ago with 1,327 yards as a rookie.

"It's really difficult to get ready for a team like this along with trying to find the matchups first of all and then to match the matchups, that makes it hard facing this offense," Joseph said.

Although the Broncos at least have the luxury of having seen Mahomes on the other side of the line of scrimmage, Joseph noted that Kansas City operated with a watered-down playbook in last season's matchup.

"When you watch (this year's) games, I think offensively they're a lot different," acknowledged Joseph. "Obviously last year in Week 17 he was probably operating under probably 35 percent of the offense."

Kansas City head coach Andy Reid also was uncertain if familiarity would help the Broncos slow down Mahomes and his offense.

"Whether it's an advantage or not I can't tell you that, I don't know that," said Reid. "But they have seen him and we'll see how it goes."

Mahomes is certain of one thing -- the Broncos will try to apply pressure to him and he must be aware of Miller at all times.

"They move him around, they try and get him different ways he can rush the passer and make plays," Mahomes said. "The thing is with their defensive front, they have weapons all over the defensive front, so you always know where Von is but you have to have a plan for their whole defense, so we're going to have a good one going in."

Denver needs to get its offense untracked against a defense that has surrendered 30.7 points per game. The Broncos won their first two games at home by a combined four points before dropping a 27-14 decision at Baltimore last weekend.

Quarterback Case Keenum has struggled in his first season in the Mile High City. He had passed for three touchdowns against five interceptions and is coming off a season-low 192 yards passing at Baltimore. Emmanuel Sanders has been his favorite target with 19 catches, but the team learned Thursday that tight end Jake Butt is done for the season with a torn ACL.

Broncos rookie running backs Phillip Lindsay and Royce Freeman have combined for 350 yards rushing and rank second and fourth, respectively, among rookie rushing leaders. Lindsay has 198 yards on 33 carries while Freeman has 152 yards.