On the other hand, he’s 41 years old with cranky knees. And while Roger Clemens is proof that 41 isn’t the end of the world — 42 doesn’t seem to be it, either — at that age, the body can go at any time.

And Johnson so far gives every sign of having crossed that threshold when he simply doesn’t have what he once did. Even in his Opening Day win, when he gave up just one run to the Red Sox and struck out six in six innings, Johnson simply didn’t look like Johnson.

He struck out batters, but he didn’t overpower them. Hitters were swinging and missing at his slider, but they weren’t hopelessly behind his fastball, which is coming to the plate in the low- to mid-90s. That’s still fast, but it’s not lightning fast, not Big Unit fast.

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His second start against Baltimore was a disaster. His third, Thursday night, was pretty much the same thing.

He left with the score tied, so he didn’t get the loss. But he gave up five runs while his teammates were scoring the same number. Had he held the Red Sox to one or two, which is what he’s expected to do over seven innings, it’s a Yankee win. So, while he didn’t get the loss, he still lost the game.

And that’s not good enough. The Yankees didn’t get him to hold the other guys to five runs. They didn’t get him to give them “quality starts” — six innings with three or fewer runs.

They got Johnson to be an intimidating and dominating starter, a flamethrower who could make the other team quit before they even got to the plate, a stud you could rely on to utterly shut down every team on the schedule.

They haven’t gotten that, not yet. Instead, they have a pitcher who’s ranged from better-than-average to completely ordinary.

And maybe it’s too early to panic, but it’s not too early to ask, where’s the real Randy Johnson?