The Oakland Raiders picked up yet another exhibition win on Thursday night, defeating the Green Bay Packers by a score of 22-21 to get off to a 3-0 record with one week left to play in the preseason.

But how much did the win actually matter?

Seeing as how none of the Raiders' regulars actually played in this game, not much.

Oakland is still facing a lot of concerns heading into 2019 regardless of its preseason success, so here are three burning questions for the Raiders following their third preseason contest.

3. Who Will Be the No. 1 Running Back?

The Raiders have a bevy of options in their backfield, and none of them are particularly tantalizing.

There is veteran Doug Martin, rookie Josh Jacobs and then Jalen Richard and DeAndre Washington.

All four of those guys are capable of getting carries in an NFL game, but, obviously, all four of them won't be playing on a consistent basis, so at some point, Jon Gruden is going to have to choose a No. 1.

Jacobs is certainly the running back of the future, but is he ready to take the reins as a featured back right off the bat? Martin is a seasoned veteran, but an injury-prone one, at that, and he is hardly the same player he was during his early days with the Tampa Bay Buccaneers.

Richard and Washington? They're solid, but not really No. 1 back material.

Chances are, this will come down to Martin and Jacobs.

2. How Much Better Is the Defense?

The Raiders had a lot of problems in 2018, as their 4-12 finish suggests, but perhaps their biggest issue was a porous defense that ranked 26th in the NFL in yards allowed and dead last in points allowed.

Oakland tried to address the gaping hole that is its defense this offseason, signing Lamarcus Joyner and Vontaze Burfict and drafting safety Jonathan Abram, but the unit still looks like it's going to be a problem.

Regardless of how much winning the Raiders have been doing through their first three preseason games, we really don't know how much better their defense actually is, and it would be surprising if they finished in the top half of the league in that category in 2019.

If Oakland wants to make a playoff push, its offense better be lethal, because its defense probably won't be very good.

1. What Type of Rapport Have Derek Carr and Antonio Brown Formed?

It's tough for a quarterback to form camaraderie with a receiver if that receiver is not even showing up, and that has been the story for Derek Carr and Antonio Brown this summer.

Brown attended offseason workouts, but he has missed just about all of training camp due to a foot issue and a battle with the NFL over the usage of his helmet and won't be playing in the preseason.

So, basically, the Raiders just added Brown in March, and Carr might not actually get the chance to throw to him for an extended period of time until Week 1.

That is not exactly great news for an Oakland club that is placing its postseason hopes on the Carr-Brown connection.