The NFL season is a long, arduous journey that can take a toll on the deepest of rosters.

Infused with talent and injected with depth at a number of positions, the Browns know this better than most.

For a variety of reasons, most of which are injury-related, Cleveland's roster has undergone plenty of churn as the season has progressed. It's really picked up in recent weeks, and it's left the team counting on "next men up" at all sorts of important places on the field. 

Ideally, these would be the players who entered the season as backups or third-string options. In a handful of circumstances, though, the Browns are relying on players who weren't even a part of the 53-man roster when the season began.

Such is life in the NFL, where there's a shortage of sympathy when these sorts of issues arise.

"That is the battle of the NFL, right? There is an old saying that if you keep them, eventually they are going to play for you, and when they play for you, they need to play well enough to win," Browns coach Freddie Kitchens said. "That is the reason I always say that if we put someone out there, he is expected to play well and play winning football.

"I am happy with the guys that we have brought in. (General Manager) John (Dorsey) and those guys have done a good job of finding people to replace guys when we lose guys, and that is part of the league, too."

Here are five who fit this distinction and have stepped up most in recent weeks.

DEs Porter Gustin and Bryan Cox and DT Eli Ankou

Ankou is the eldest statesman of this trio … and he's only been here since Oct. 22.

The third-year defensive tackle immediately joined the defensive line rotation shortly after Daniel Ekuale was placed on injured reserve and has seen his responsibilities increase in the wake of Devaroe Lawrence's release and Larry Ogunjobi’s one-game suspension. The former Jaguar has appeared in five games, started the Dolphins game and played a significant role in last week's loss to the Steelers.

Signed to the practice squad Nov. 4, Gustin was added to the 53-man roster shortly before Cleveland's Week 12 win over the Dolphins. The undrafted rookie out of USC collected his first NFL sack in that game and, because of injuries that limited the snaps of Olivier Vernon and Chad Thomas, led all defensive ends in snaps last week against the Steelers.

Cox was close behind in the Steelers game and was similarly active one week earlier against the Dolphins. The third-year defensive end joined the Browns on Nov. 13 after spending his previous years with the Panthers. Perhaps expediting his level of comfort within Cleveland's defense is his relationship with defensive coordinator Steve Wilks, who was in the same position with the Panthers during Cox's rookie year in 2017.

Cox, Gustin and others are being called upon to help make up for the loss of Pro Bowl pass rusher Myles Garrett, who is suspended indefinitely. 

"I am not going to use the word difficult. I think we have to be creative in what we are trying to do," Wilks said. "We just have to continue to try to mix it up a little bit, and guys have to find ways to execute and finish."

This group represents three of five defensive linemen who weren't on the team to start the season, joining tackles Brandin Bryant and the recently signed Justin Zimmer.

"We still have to find ways to make plays," Wilks said. "Just trying to generate things up front, moving guys around, trying to create different pressures. We are never going to make any excuses, but when you look at it, we have maybe four or five guys that are here on the 53 that were not a month ago. We are not cancelling games. We have to find a way to get our guys in position to be successful, and that starts with me."

S Juston Burris

Burris was with the team throughout training camp but was waived when rosters were trimmed to 53 players. After a short stint with the Raiders, Burris rejoined the Browns 48 hours before a Week 3 game against the Rams in which the entire starting secondary was sidelined with various injuries.

When those starters slowly returned to the lineup, Burris understandably saw his snaps decrease. The abrupt release of Jermaine Whitehead after a Week 9 loss to the Broncos and Morgan Burnett’s season-ending injury have thrust Burris back into a role in which he's being tasked to play almost every snap.

Burris has seven starts and is second on the team with two interceptions.

"Juston came into a tough situation earlier in the year," Kitchens said last month. "He was here less than 48 hours for us, played in a game for us and played well. It says a lot about his football character from the standpoint of being able to focus and concentrate."

TE Stephen Carlson

Carlson has been with the team all season but didn't join the 53-man roster until Week 9. He's been a key member of a Cleveland tight end room that's been without its top pass-catching option, David Njoku, since Week 2 and has seemingly never had everyone healthy at the same time. He hauled in his first NFL touchdown in the Browns' win over the Steelers and has provided a handful of other big catches.

In last week's loss to the Steelers, Carlson delivered a lethal stiff-arm after a catch in the first quarter and made an athletic play in the fourth quarter to down an Austin Seibert pooch punt inside the 1-yard line.

"Stephen is a good, dependable, you know where he is going to be, you know he is going to make the plays that are there to be made and he is reliable," Kitchens said. "I am really, really happy with what he had given us offensively and from a special teams standpoint. Sometimes you need guys just to go in and do their job on special teams, as well, and he has done a good job in all areas. I am very happy with what Stephen has brought to us."