Welcome to a key week in which some bubbles will pop and others will float on.

In Week 4 of the preseason, few if any, of the Broncos starters will play because on Sept. 1 the Broncos will have to cut their roster down from 90 players to 53. Many of these players have already determined their respective fates but a handful are still battling for the last few spots on the roster.

We take a look at five key Denver Broncos who could be sent packing on Saturday.

Paxton Lynch: One of the few things you can learn about a quarterback in the preseason is whether or not the game is too fast for him, and boy is it too fast for Lynch. On every dropback, Lynch looks more like a fan that got to be the Broncos’ quarterback for a day and less like a first-round pick.

Against the Minnesota Vikings, Lynch looked completely lost which, paired with Chad Kelly’s excellent performance, pushed him down the roster to the No. 3 quarterback. Over the last two preseason games, Paxton went up against third-stringers and players who won’t make their teams, and still performed terribly. He completed 8-18 attempts for 78 yards. To put that in perspective, Lynch averaged 4.33 yards per passing attempt, while the undrafted Phillip Lindsay averaged 5.73 yards per rushing attempt. If Lynch makes the roster, it’s purely because of draft pedigree and stubbornness to admit mistakes by John Elway.

Devontae Booker: Booker entered the preseason as the presumptive Week 1 starter. But, his performances have been disappointing, while the running backs behind him have lit it up. Royce Freeman, Lindsay, and Andy Janovich are all slam dunks to make the final roster and few teams ever carry more than four running backs, meaning there’s one spot left between David Williams, De’Angelo Henderson, and Booker.

Booker has the edge on Williams for sure, but he’s neck and neck with Henderson. Booker has draft pedigree, experience and his starter label on his side, and Henderson has the performances and stats on his. In the end, Booker probably beats out Henderson because of his position on the depth chart before the season, and the fact that Henderson’s value has been minimized by the addition of Lindsay as another back who can catch passes from the backfield.

Isaiah McKenzie: The former Georgia speedster finds himself in a tricky position entering Week 4. He had a great punt return for a touchdown against Minnesota but hasn’t done anything else before, or since. He spent a lot of time during the offseason attempting to fix his fumbling woes, to no avail. Against the Bears, he fumbled again, this time on his lone reception of the preseason, which was a loss of two.

Add the signing of talented punt returner Adam “Pacman” Jones to the mix, and the writing appears to be on the wall for McKenzie. His best chance at being safe is once again draft pedigree. Are the Broncos willing to give up on this guy they drafted just last year?

Brendan Langley: Speaking of giving up on players after one year, Brendan Langley finds himself in a very similar position to McKenzie. Langley has been a clear weak spot in the Broncos’ secondary throughout all three preseason games, but it would be a black eye on Elway’s record to cut a third-round pick after just one season.

The Broncos drafted Langley knowing he was raw but thought they could coach him up and take advantage of his athleticism. Langley has also been the Broncos’ best gunner on special teams, which is his best chance to make the roster.

Denver will bring five or six corners into the season with them. Chris Harris Jr., Bradley Roby, Isaac Yiadom, Tramaine Brock, and “Pacman” should all make the roster, meaning Langley needs to make a splash in the final preseason game to avoid the cut.

Su’a Cravens: Entering the preseason there was tons of hype surrounding the hybrid safety/linebacker, and even talk of him possibly replacing Darian Stewart at strong safety. Then, injuries sidelined Cravens, and he now finds himself on the verge of being cut.

Cravens was selected n the second round of the 2016 draft by Washington as a money-backer (linebacker/safety hybrid). He had a fantastic rookie season but sat out the 2017 season contemplating retirement. Washington then traded him along with a fourth-round pick and a fifth-round pick to Denver for a fourth, two fifths, and 2020 conditional sixth-round pick.

Despite practicing for the first time Monday, Cravens has a good chance to make the team due to the lack of depth at safety, his high talent level, and the amount of capital the Broncos have invested in him.

As Vance Joseph said in camp, “He hasn’t been with us. The position he plays is the dime [linebacker] spot. It’s a critical spot for us, so absolutely he has to play eventually so we can see what we’ve got in him.”

He better make every snap count this Thursday in Arizona.

The Broncos face the Arizona Cardinals at 8 p.m. MST this Thursday in a game which will determine the fate of these five, key players, along with many others.