PHILADELPHIA—One of the heroes in last night’s 5-4 walk-off win over the Nationals, Domonic Brown, danced off the field after circling the infield dirt like an airplane.

The other, Ryan Howard, left with a limp. In the eighth inning.

Inspiring as the moment may have been last night – imagine the possibilities of a productive Howard-Brown tandem! – reality had set in by afternoon today.

“I was waiting for him to come because I wanted to see how he felt,” manager Charlie Manuel said. “If he’s hurting, I’ll have to change my lineup.”

The Phillies first baseman’s condition, described by GM Ruben Amaro, Manuel and Howard himself as “arthritis" of his left knee, is chronic, degenerative and, ultimately, prohibitive.

The extent to which he’ll be limited remains to be seen. The Phillies will find out; Howard’s only in Year 2 of a $125 million extension from 2010. Amaro yesterday admitted that his contract may be difficult to move. Howard’s condition is among the biggest reasons why.

Early inklings are in. Howard’s second-inning shot yesterday was his first in 16 games, tied with the second-longest drought of his career. He went 3 for 3 with a walk. By the eighth inning, he was hurting.

“If you notice, the longer we were playing and he was on the bases, he was definitely kind of limping at the end of the game," Manuel said.

It was impossible to not notice. The Phillies slugger, seemingly on the precipice of a breakthrough, held back by weakness in a power hitter’s most crucial area: his back leg. His power leg. As apparent were the implications.

“He hasn’t used his legs for quite a while, his backside, what you’d call pushing off,” Manuel said.

What do to with him?

The plan seems to vigilantly monitor his play and encourage communication.

“If it bothers him, if it hurts, he’s the one that’s feeling it,” Manuel said. “I can’t feel it. How much it bothers him, I guess he tells us by the way he plays and us watching.”

Long stretches of ineffectiveness may force the Phillies hand. But if Howard is plodding along, hovering just above an acceptable level of play yet experiencing pain, the organization needs need him to be forthcoming, how, at times, Chase Utley and Roy Halladay weren't Otherwise, they risk catastrophe.

If Howard is deemed unfit to continue, either by his play or his word, how the Phillies handle him will be interesting. It’s hard to imagine a DL stint accomplishing much. Likely not much more than putting the problem on temporary hold. Shutting him down for the season is, in essence, a grander form of the same strategy – likely with the same results.

Maintenance, then, will be key.

Do they platoon Howard? He’s quite famously struggled vs. lefties, who make up only 25-30 percent of all big league starters. That lets organization to feel it’s getting use out of its $25 million a year player. John Mayberry Jr. could be the short-term option with Darin Ruf maybe the long-term fix.

But medical treatment will be vital to his longevity.

What, exactly, can be done to preserve his knees?

“I think there’s things that definitely, probably, when he gets some time off or something like that that they can take care of him. I hope they can.

“Maybe going ahead, there’s things that hopefully he can do that he won’t have so much pain.”

Manuel said he thinks Howard can hit “30 to 35” homers this year. Last night’s was his eighth.

“I think he can hit that. I think he can do that. I’m usually right on or close. I don’t miss by much.”

The manager then made sure to note the ominous asterisk hanging overhead, not only for his prediction, but, maybe, for a big part of the future of the organization.

“Lot of ifs in there, though.”