Of all the things an NFL center must keep track of, sometimes the most obvious is overlooked. After checking for the defensive scheme, organizing and communicating the blocking plan, then taking one last peek to adjust to blitzes, Jets rookie Nick Mangold lives by one rule.

“Always know the snap count,” he said, “because they know when you don’t.”

There are few things more embarrassing than standing in front of 80,000 or so fans with the football still in your hands after the other 21 players on the field have jolted into action. There’s no chance to point across the line and blame a twitch by a defender, nor is there a reason to look up at the scoreboard to see if the refs got the call right. The evidence is humiliating and overwhelming.

It’s a lonely feeling Mangold has not experienced this season. The Jets center has found another way to stand out - by quickly developing into a leader despite being the youngest member of a young offensive line. The Grizzly Adams beard he’s been ignoring since training camp hides the baby face of a 22-year-old, born a month after fellow rookie and fast friend D’Brickashaw Ferguson at left tackle and more than a decade after 11-year veteran Pete Kendall at left guard.

Mangold’s meteoric rise makes him one of the more surprising candidates for NFL Rookie of the Year, topped in improbability only by the Saints’ Marques Colston, a Hofstra product drafted in the seventh round who leads the league in receiving yards. In a draft class that featured a pair of Heisman Trophy winners and a can’t-miss offensive tackle who the Jets picked 25 spots ahead of Mangold, the Centerville, Ohio, product quickly is becoming not only one of the top rookies but a top player at his position.

And he wasn’t even supposed to play much this year. In fact, he wasn’t even supposed to be a Jets pick. They added that 29th selection when they traded defensive end John Abraham to the Falcons in March. That pick originally belonged to the Broncos, so the Jets got Mangold third-hand.

“It’s crazy,” Mangold said of his path. “Mind-blowing.”

The Jets already had a Pro Bowl center in Kevin Mawae when the 2005 season ended. But in March, a month before the draft, he was cuts and wound up signing with the Titans. The Jets signed veteran Trey Teague to take his place and, after taking Mangold, probably figured Teague would be able to groom their future snapper.

But Teague broke his ankle during offseason training - he broke it again earlier this month and has been placed on IR - and it became clear by the end of the Jets’ minicamp in July that Mangold would be thrown into the center of the action. Kendall, who played center in 2005 when Mawae was injured, began working with Mangold on recognizing the complicated NFL defenses and blitzes to which a center must adjust. Others on the offensive line chipped in as well, helping add their experiences and knowledge to the process.

It takes a village. And now that village has a new mayor.

“He always looks good, always manages to make good decisions,” right tackle Anthony Clement said of Mangold. “The center does have to control and command the line, and he pretty much does that now. He had the help of Pete in the beginning, but Nick’s doing a real good job now. Pete sees that and he’s just letting him do his thing.”

Although just more than halfway through his rookie season, Clement said Mangold has the makings of a future team captain. “He pretty much acts like that now,” the nine-year veteran said.

Mangold’s sense of humor may be more agile than his 6-4, 300-pound frame. After a crazy lateral-filled game-ending play against the Colts this season, he was asked when was the last time he had touched the ball: “Every play,” he snapped. Asked when he started to feel comfortable with his role as shepherd of the line, he replied “Probably March 2007.” During a training camp talent show, when Ferguson developed stage fright in the middle of a joke, Mangold pounced to his buddy’s aid and delivered his own punchline.

The Jets are more interested in the O-line than in one-liners, and Mangold is a crowd-pleaser in that regard, too. He may not have the reputation of Mawae, but he is making a name for himself in the tiny circles that discuss interior line play.

In the last two games, Mangold has battled two of the most experienced, dominating nose tackles in the NFL. Against the Browns he held Ted Washington to one tackle, then last week he battled Vince Wilfork of the Patriots and held him to three tackles. That most recent performance, which included a brief sideline pitstop after being poked in his right eye, drew praise from Jets coach Eric Mangini.

“We always talk about the characteristics of the players and we talk about toughness,” Mangini said. “He got poked pretty well there and missed two plays and really would have liked to have just missed one play, but he did a nice job. Vince [Wilfork] is a really good nose tackle, and to have him over you the whole day and to meet that challenge, that is a solid effort.”

He won’t have a nose tackle hovering over him this week because the Bears play a 4-3 defense, but he will be staring out at middle linebacker Brian Urlacher. He’ll also be in charge of calling schemes against the top defensive unit in the league.

“He constantly has to make good decisions and do some things in the front in terms of communication, getting everybody lined up,” Mangini said. “I really am happy with the progress he continues to make.”

Mangold said he has no special talents that have allowed him to become a center. In seventh grade he was put at the position by a coach, and he never left. He was a three-year starter there in high school, a three-year starter for Ohio State, and now a three-month starter for the Jets. And he’s still learning.

“Being in my position, I never feel like I know enough and I never feel comfortable where I’m at, which keeps me working,” Mangold said. “Pete, A.C. Brandon [Moore] and Trey have done a great job of making me feel comfortable out there, but it still feels kind of weird. This is the NFL and here I am being able to have a part in it.”

All while trying to remember the snap count.