Three things to watch when the Jets play the Giants in their first preseason opener Thursday night:

Sam I am

Sam Darnold has lit up the practice field on most days in training camp. Can he keep it up in a game? Darnold and the starters likely will only play a series or two, but a good drive will help their confidence as they learn Adam Gase’s system.

Kids’ corner

2. The biggest question mark on the team is at cornerback where the Jets have little depth. Beyond Trumaine Johnson, Darryl Roberts and Brian Poole, everyone else is playing for his roster spot. Does anyone do something to improve his chances?

Return on investment

3. The Jets let All-Pro Andre Roberts walk in free agency and now are searching for his replacement both as a kick and punt returner. Trenton Cannon is listed as the top kick returner and undrafted rookie Greg Dortch as the top punt returner. These are positions that are impossible to judge in practice. Players can sink or swim in preseason games.