Alex Rodriguez locked in on a Brian Matusz offering Monday and unleashed the instantly-recognizable swing that has always seemed too easy and too effortless, to do any real damage.

But we know better by now. Rodriguez cocked his head to follow the flight of the ball then flashed his trademark “Trust me, I’m awesome” glance into his own dugout: always his sign that he knows he got all of it.

If it were the old Stadium, the ball would have landed snugly in the non-bastardized version of Monument Park. In the new house, it hit the back wall of the visitor’s bullpen. A flick of his wrists and the ball traveled 429-feet.

He can still be an amazing player to watch when you catch him at the right time.

Alex Rodriguez is 35 years old now, may or may not have a degenerative hip issue, and has had trouble staying on the field for extended periods this season. Looking at his numbers, it’s fair to assert that the 2010 season represents the beginning of A-Rod’s decline.

This wouldn’t be as premature as some people think. He’s been in the Majors since he was 18, accumulating over 10,000 at-bats in the process. That’s a lot of innings on the field, a lot of road trips, a lot of swings that look so free and easy, but are really violent acts of physics.

The man who only four years ago hit 14 homers in one April now sits at 22 homers as we creep toward mid-September. Keeping his streak alive of 12 straight 30-plus home runs seasons would take a tear I’m not sure is in him.

But then again, we were thinking that around this time last year as well. Then came the two-homer, eight-RBI inning that closed the regular season, setting the table for an outstanding postseason that took his baseball reputation off of life support.

Make no mistake: The Yankees will not win the World Series in 2009 without Rodriguez. Mark Teixeira played that postseason like his family was secretly being held for ransom, and key role players like Nick Swisher, Phil Hughes, and Robinson Cano all struggled.

For all the crap A-Rod has taken from both the A-Rod haters, Yankees fans, and the large faction of A-Rod haters who are Yankees fans, he doesn’t get enough credit for how he carried New York through three rounds of playoffs last season.

The Yankees will make the playoffs again in 2010, with a whole host of new challenges. The roster is different and the opponents could differ as well. But New York will still need a big-time performance from Rodriguez.

The question becomes, does he have it in him? The pessimist in me wants to say no, that A-Rod will struggle in an ugly ALDS knockout, come into camp in February and proclaim he never was healthy in 2010.

“I never really felt comfortable at the plate last year,” he would say, repeatedly pursing his oddly-shaded lips. “But I’ve worked hard with K-Long all winter and I’ve never felt better heading into a season.”

It’s almost too obvious.

But then again, hasn’t A-Rod earned the right for us to purge these negative thoughts associated with him and October baseball? I’m sure he would say yes, but there are probably many people—myself included—who would like to see him do it again before clearing him of past sins forever.

The bigger question may be this: Is A-Rod still a top-tier player at this stage of his career? His season has been an anomaly: He’s on pace for the worst power and slugging numbers of his career but he’ll still finish with well over 100 RBIs.

Call the RBI a flawed stat if you want but it represents physical proof that he’s still a premier run producer. What’s now unclear is if he will be a dynamic player anymore, the type of guy he was last October, where you thought something special was going to happen every time he came to the plate.

The Yankees put all their weight on A-Rod to bring home a World Series in 2009 and he delivered. If they lean on him again in 2010, can he deliver at that same level?

Just 12 months later, it’s not unfair to ask for similar greatness. But the possibility exists that the weight is too much for a body that remains willing, but may no longer be able.

Dan Hanzus writes the Yankees blog River & Sunset and can be reached via e-mail at dhanzus@gmail.com. Follow Dan on Twitter @danhanzus.

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