New Denver Broncos quarterback Peyton Manning returns to the field on Saturday night after a brief appearance in the team's preseason opener. He completed four 4-of-7 passes for 44 yards with an interception off a deflected pass in his debut.

Manning should see a little bit more action as he attempts to get ready for the regular season after missing all of last year with a neck injury. Here are some things to watch for against the Seattle Seahawks to gauge how close the legendary QB is to his old form.

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Endurance

The difference between working out individually or at practice and actually playing in an NFL game is enormous. So for a player who has been sidelined as long as Manning, getting back up to full speed is a gradual process.

He needs to build his endurance back up so he's able to have the energy level necessary to lead an offense during a two-minute drill. That's especially true for somebody who's going to play half his games a mile high in Denver.

Keep an eye on how Manning performs as he gets a little deeper in the game. He probably won't be at full strength quite yet, but he better be getting pretty close with the regular season right around the corner.

Arm Strength

In the opener, it was immediately clear Manning didn't have the same amount of zip on his passes that he did during his days with the Indianapolis Colts. He still featured pinpoint accuracy, but the arm strength left a lot to be desired.

Only Manning knows if he was actually giving full effort on those throws or holding back a little bit as he gets more comfortable. He definitely needs to pick up the pace before the regular season begins, though, or defenses will start jumping more routes.

Manning never had the most powerful arm in the league, and his accuracy will allow him to make up for some loss in strength, but not for as much as fans saw in the first game.

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Pocket Confidence

After enduring an extended recovery process from a major injury like Manning's, it's human nature to become a little gun shy for a while. Even doing something like standing in the pocket—which he's done for nearly his entire life—just doesn't feel the same.

Manning wasn't sacked in the first game. That actually might be a bad thing. Getting hit one time by a massive defensive end and being able to bounce right back up would help him feel like he's back in the saddle again instead of worrying about the injury.

The first game illustrated that he's not back at his usual All-Pro level quite yet, but that's what the preseason games are for. If he makes a little progress in each of these three areas on Saturday night, he'll be on the right track for Week 1.