When the New York Giants play the Pittsburgh Steelers on Friday night, it will be the team’s first preseason game. Eli Manning, Odell Beckham Jr., Ben Roethlisberger, and other big names won’t be playing a single snap. For casual fans, it may be hard to get excited for such a game. However, there is much to glean from full-speed action.

Besides units that will be worth monitoring throughout this contest, here are five players to keep an eye on during Friday’s game.

Wide Receiver Dwayne Harris

Harris is not at risk of being cut. He has a role ironed out on this team. But he falls into a weird middle ground in terms of offensive usefulness. His performance on offense will tell us how the team feels about him in that role, and in turn, tell us how the team feels about the younger receivers on the depth chart. Let’s put it this way. If Harris lines up a lot in offensive formations, that’s bad for Roger Lewis, Darius Powe, and the rest of the receivers on the roster bubble.

Left Tackle Ereck Flowers

Regardless of opponent or situation, Ereck Flowers needs to prove himself. He needs to do so every time he takes the field in a Giants uniform. He needs to beat his opponent in practice drills, in camp exercises, and especially in game action.

Offensive Lineman D.J. Fluker

Fluker is the swing man and real question mark along the New York offensive line. He can play guard or tackle. He may start or be a bench player. Each preseason game will be a test of where he fits best on this roster. Flexibility itself may end up being his best asset, which is a fine conclusion.

Tight End Will Tye

Where and when Tye plays in preseason game one will tell us a lot about how the Giants feel about his future. In a weird twist, it will probably be a stronger vote of confidence if he doesn’t see the field much at all. That may mean NY wants him as their main backup to Engram. Of course, that may also mean the team has no place for him at all. This will be tricky to monitor to determine where Tye’s future stands.

Defensive Tackle Dalvin Tomlinson

More than any of the other rookies, Tomlinson is in a real fight for playing time. Although he doesn’t need to win a job during this single game, his first action on the field will be telling. How quickly did he learn the schemes? Can he hold up against a fast-paced and prolific offense? Will his mistakes be correctable or signs of bad trends? With a number of veterans also competing for defensive tackle snaps, Tomlinson has his work cut out for him against Pittsburgh.

Many more players have a lot riding on each preseason contest they get into. These five, though, are hinges of a sort for how the Giants’ roster is going to shake out come September.

Todd Salem is the New York Giants Lead Writer at Pro Football Spot. He is also a Contributing Editor at BuzzChomp, a Staff Writer for NFL Spinzone, and a Featured Columnist at College Sports Madness, among others. Follow him on Twitter @sportspinata