The Carolina Panthers will remain at home in their preseason finale against the Pittsburgh Steelers on Thursday. It will be the final game for the Panthers before they have to trim their roster to 53 players.

The Panthers aren't expected to play many of their starters—if any—when they take on the Steelers. As expected, Cam Newton won't suit up this week as he continues to recover from a foot injury he suffered last week against the New England Patriots.

Newton's preseason debut versus New England was the first time he had taken a snap in a game since Week 14 of the 2018 season. The Panthers' franchise quarterback had undergone shoulder surgery during the offseason. As a result, Carolina erred on the side of caution with its handling of him in training camp.

Due to the starters seeing limited playing time this week, the players on the roster ‘bubble' will have a chance to earn a spot on the team. There are still quite a few players who still have to earn their keep for the Panthers.

Here are the three key players to watch in the Panthers' preseason finale against the Steelers.

3. Reggie Bonnafon

Heading into the Panthers' final preseason outing, Ron Rivera will need to decide what to do at the running back position. Among the running backs who are competing for a roster spot, Reggie Bonnafon is fighting to remain with the team.

The Panthers signed Bonnafon as an undrafted rookie last season, but the running back spent most of his time on the practice squad. Through three preseason games, the Louisville product has made a solid case to stick on the active roster.

Bonnafon has carried nine times for 44 yards in his first three exhibition games this preseason. The 23-year-old running back also flashed his ability to catch passes, with 10 receptions for 93 yards.

Prior to the preseason finale, Bonnafon trails Christian McCaffrey, Cameron Artis-Payne, and Jordan Scarlett on the depth chart. The second-year rusher will have to leave it all on the field on Thursday night to crack the final roster cuts.

2. Jordan Scarlett

Along with Bonnafon, rookie Jordan Scarlett will have to turn the heads of the coaching staff to cement his role with the offense. Carolina used their fifth-round pick in this year's draft to select Scarlett out of Florida.

Therefore, Scarlett almost automatically holds the edge on Bonnafon for the third running back spot on the depth chart. The rookie ball-carrier has played in two preseason games and has been solid to date.

In his first two preseason games in the NFL, the former Gator has compiled 59 yards on 18 rushing attempts. Scarlett has also brought in two receptions for 22 yards.

The Panthers don't have any issue with their starting running back in McCaffrey, but the team still needs depth behind him. Artis-Payne will be the first to vulture some carries behind McCaffrey but the rookie could wind up working his way up the depth chart as the season progresses.

1. Will Grier

There's no doubt that all eyes will be on rookie Will Grier when Carolina takes the field against the Steelers this week. Grier was taken in the third round of this year's draft to develop behind Cam Newton.

Furthermore, Grier will begin the season as the team's third quarterback behind Kyle Allen. Allen has experience in the offense and the rookie signal-caller hasn't exactly lit it up in the preseason.

The North Carolina native has completed 23 of his 43 passing attempts for 196 yards, one touchdown, and two interceptions. The Panthers third-round selection will want to limit his turnovers in the team's preseason finale on Thursday.

Taylor Heinicke will likely see some snaps under center, but the third-year quarterback is the odds-on favorite to be released by the team. Grier will need to show the team it didn't make a mistake taking him in the early rounds of this year's draft.