ENGLEWOOD, Colo. -- The Denver Broncos have some big questions that may not receive an answer to before they run out of games this season.

One of the biggest, given the investment they've made at the position, is the inability to get the ball to the wide receivers.

The Broncos are a team that leans on its running game -- despite what it showed during a dismal 18-yard rushing effort in Sunday's loss to the Las Vegas Raiders -- but they still should have a far easier time of getting the ball to a talented wide receivers group.

The Broncos used a first-round pick to select Jerry Jeudy in the 2020 draft, signed Courtland Sutton to a four-year, $60.8 million deal earlier this month and Tim Patrick to a three-year $34 million extension a day earlier. But scan the league's rankings and you have to go all the way to 48th to find a Broncos wide receiver (Sutton) in catches, to 41st in yards receiving (Sutton), to 67th in yards gained after catch (Jeudy) and to 30th in touchdowns (Patrick).

The Broncos haven't found the right route combinations to give their receivers room to work consistently or to protect the quarterback well enough to get them the ball.

"Our passing game just has to be better on all fronts," coach Vic Fangio said before the Broncos gained a total of 158 yards in the loss to the Raiders. "We have to throw it well enough. We have to catch it well enough, we have to scheme it well enough as coaches. We have to pass protect well enough and we have to have good action with our passes. It's from A to Z on that. It's not just one guy or one thing."

The only Broncos player who has averaged more than 14 yards per catch this season is KJ Hamler (14.8), and he hasn't played since suffering a torn ACL in his left knee during the Broncos' Week 3 win over the New York Jets.

"It's a culmination of things," Sutton said after Sunday's loss. "... It's just a combination of a lot of things."

Indeed it is. Hamler's absence, as one of the Broncos' fastest players and one of the fastest ones in the 2020 draft (he was Denver's second-round pick at 46th overall), has impacted how defenses have played the Broncos' other receivers at least some. Hamler was often the player, in the season's early going, who could pull help away from the others in the deep part of the field.

Several defensive coaches have said in recent weeks the Broncos often can't protect their quarterback well enough to get the receivers to the top of routes, especially in their three wide-receiver look. So the quarterback, whether it's Teddy Bridgewater or Drew Lock, is often on the move before the routes are done, which means checkdowns to tight ends and running backs.

Toss in a drop or two of late, including one from Jeudy on Sunday, and it all continues to vex the Broncos.

Before Sunday's loss, the Broncos top four wide receivers in the rotation -- Sutton, Patrick, Jeudy and Kendall Hinton -- had 27 catches combined in the previous four games. Sutton then had four catches against the Raiders for 33 yards, while Patrick had two for 18 yards.

Jeudy's 40-yard catch-and-run early in the second quarter against the Raiders was his longest play of the season, and he had a 14-yard catch later in the same field-goal drive. He didn't catch a pass for the remainder of the game as the Broncos finished with 40 offensive snaps.

Offensive coordinator Pat Shurmur has said "each game is different," but the Broncos, despite their inclination to run the ball, have actually, even with Joe Burrow's 525-yard effort Sunday, attempted more passes than the Cincinnati Bengals this season -- 488 compared to 486. The Broncos trail the Bengals by more than a yard per attempt -- 6.1 compared to Cincinnati's 7.3.

"[We have to] figure out what may not have worked well and try to work on it," Sutton said. "... That's our job."