Jayson Werth, left, high-fives teammate Ryan Zimmerman after a victory over Arizona at Nationals Park. (Patrick Smith/GETTY IMAGES)

All season, Washington Nationals fans have watched Jayson Werth’s every move, just as rubberneckers throughout baseball have frequently glanced toward D.C. to see who was hurt and how badly in his $126 million car crash of a contract.

Would Werth regain his former career-long standard of play this season without the comfort of cozy Citizens Bank Park and the support of the Philadelphia Phillies’ lineup? For that matter, would Werth ever play like himself again, or had the contract somehow undone him psychologically as that unlucky $126 million number did to Barry Zito and Vernon Wells?

And if Werth ever did play to his old form — okay, more likely his form if you exclude a career year in 2010 — what impact would it have on the Nats? Would he carry the team, ignite the lineup or bring Phils swagger to D.C.?

Well, we may have the answers. We just didn’t notice it. Since the all-star break, over his past 41 games, a full quarter of a season, Werth has duplicated his career statistics (as well as his numbers in Philly from 2007 to ’09 which included a World Series title) as closely as a player ever could.

Non-geeks, please cover your eyes for a paragraph. His slash line since the break is .273 with a .364 on-base percentage and a /.461 slugging percentage. For his career it’s .265/.361/.467. For 2007-09 in Philly, with a bit of help from Citizens Bank, it was .276/.376/.494. But when the Nats signed him, they knew to factor in a change of ballparks. Werth’s power numbers during the period (seven homers, 15 extra-base hits), walks (20) and even RBI (20) have been right at his career norms, though a tad light in RBI.

This leads to several conclusions, some encouraging, some not.

Like many, I knew Werth had said he would try to make the second half of the season a fresh start, so I watched him with that in mind. And I thought he was playing better, creditably, but still inconsistently and without contributing a great deal beyond a fine attitude, hustle, smart base running and above-average defense.

By accident, playing with other stats, I realized I’d been watching the Real Werth at the plate for nearly seven weeks, including two walks, a single and a 420-foot homer Thursday.

Yet he didn’t seem like anything more than a good right fielder with a determined streak, including an 11-pitch leadoff walk that began a six-run, bottom-of-the-ninth comeback win against the Phils.

With Werth at his worst before the all-star break, the Nats were 46-46. Since then, with Werth playing 41 of 44 games (through Friday), they’re 17-27 and seem adrift under Davey Johnson, bereft of offense no matter where Werth bats.

That’s it? That’s all the impact he has?

At least he’s holding up his end of the deal, performing at his normal level. For pros, “try hard” should be a given; “produce” is the measure. Werth is now doing it. If the Nats paid far too much, it’s on them and GM Mike Rizzo, the father, grandfather and godfather of the signing.

Of course, the Nats admitted from the first day that they had deliberately overpaid Werth. Why? It was the only way they could get him. It set a precedent that future free agents might follow. It blew up the idea that the Lerners still wouldn’t spend. And Werth supposedly brought intangibles that would show up more broadly throughout the team, not just in stats.

Rizzo even conceded he would be satisfied if the Nats got “five years” of prime Werth, plus some partial value for the $42 million he would get in 2016 and ’17. But by then, the Nats would be winning, drawing more fans and overpaying would simply be a costly but necessary part of the turnaround strategy. So, it was like a five-year, $80 million deal with a giant “never again” asterisk.

Even viewed that way, as generous a perspective as could be concocted, the Nats and their fans, as well as Werth, are going to have to come to terms, constructively or irritably, with the probability that the Werth they’ve seen since mid-July is the Werth they’re going to get — for a long time.

What if Jayson rips up September? That would mitigate the harm of a bad start and make ’11 more like a typical Werth year; it probably won’t change our core conclusions after watching him every day. Werth’s not a dominant star. But who said he was? He has made one all-star team, inched into the top 10 in MVP voting once and never quite had 100 RBI (99).

For many more years, fans will debate Jayson’s worth. But the worst-case scenario, that Werth was simply a bust, has probably gone off the table. The Nats added a valuable core piece to their team for a long time to come.

But the opposite is also true. When a man plays up to his customary standards, but few even notice it and the team plays poorly, the best-case scenario, with Werth as transformational catalyst, is likely an illusion, too.

The true Werth has finally arrived in D.C. — and he’s doing his job. You just have to look a little harder than expected to notice him.