ALAMEDA — Raiders coach Dennis Allen liked what he saw during the one-month stay at the Napa Valley Marriott.

“I thought it was a good camp,” Allen said after the Raiders’ 19th and final training camp practice Wednesday. “I thought our guys came out here and worked, and I thought we got better. I thought we got a good evaluation of what we have here in this camp right now and we’re going to do everything we can to try and improve this football team.”

Having returned to the club facility, the Raiders hold a walkthrough Thursday which is closed to the media, then play their third preseason game when they host the Chicago Bears at O.co Coliseum at 7 p.m.

With training camp over, it’s worth revisting five questions posed a month ago in anticipation of the Raiders beginning the 2013 season in Napa.

1. Can Matt Flynn pass well enough to move the offense?

Still to be determined. Flynn led a textbook two-minute drill to lead the Raiders to a touchdown at the end of the first half against New Orleans. He has shown the ability to escape trouble, complete short and medium-depth passes to keep drives alive.

In practice, Flynn’s passing has been hit and miss, and it’s an open question as to whether he could carry the team with his arm if the need were to arise.

2. How soon can cornerback D.J. Hayden make an impact?

We get at least a partial answer to that question Friday night, when Hayden opens as a starting cornerback against the Chicago Bears. He had interceptions on consecutive days during closed practice sessions this week and Allen believes his coverage ability to be exceptional.

Hayden hasn’t really laid a lick on anybody since November of last year, however. He could get his chance Friday against 6-foot-4, 230-pound wide receiver Brandon Marshall.

3. Who starts on the offensive line other than Jared Veldheer and Stefen Wisniewski

Scratch Veldheer, who could miss nearly half the regular season (or more) after having surgery to repair a torn left triceps. For now, it’s Alex Barron at left tackle, Lucas Nix at left guard, Wisniewski at center, Andre Gurode at right guard and Khalif Barnes at right tackle.

It’s a fluid situation, however. The Saints sacked Flynn five times in the first half in the second preseason game, and the Raiders will be watching the waiver wire closely. There may be a starter or two up front who isn’t yet on the roster.

4. Will dumping the zone blocking scheme revive the running game and Darren McFadden?

So far, McFadden has carried eight times for 22 yards in two preseason games — a line that’s all too similar to 2012 while hesitant in a zone scheme. McFadden always shines in practice because defenses can’t tackle to the ground.

McFadden and Allen say they aren’t concerned. Maybe they’re right. But a few nice runs Friday night would not only be greeted with cheers but huge sighs of relief from the fan base.

5. Can the defense come together with so many new faces?

The Raiders are getting more healthy on defense, but there still has not been a single day where the projected starting 11 has lined up together. Defensive tackles Vance Walker and Pat Sims have returned from injury (although Sims won’t play against Chicago) and their presence and ability to control the run and collapse the middle will be crucial to any success.

As with every other area on the Raiders, we’ll learn more in the first half of the season opener on Sept. 8 in Indianapolis then in the six weeks leading up to it.

For more on the Raiders, visit the Inside the Oakland Raiders blog at ibabuzz.com/oaklandraiders. Follow Jerry McDonald on Twitter at twitter.com/Jerrymcd.