Mike D’Antoni’s job with Lakers is to sell his offense to Dwight Howard

In one corner of the Lakers’ practice gym, even on one crutch, Mike D’Antoni was jumping through the roof.

In another corner, Superman was stuck to his seat.

At his first news conference as new Lakers coach Thursday, D’Antoni was all smiles and giggles and awe.

“It was an unbelievable feeling of, ‘I’ve got a real shot,’ ” he said of his surprise hiring. “This is really good, this is fun, the stakes are high, this type of team ... what’s not to like?”

PHOTOS: D’Antoni introduced as Lakers new coach

Meeting the media on a nearby bench, Dwight Howard was all shrugs and sighs and caution.

“It’s just the first day,” he said flatly. “He came in, he talked to us, we ran a couple of offensive plays, that’s it.”

The Lakers’ coaching drama has ended, but there could be another thriller looming if the new coach can’t sell the only Laker who needs to be sold. On a day when nearly everyone in a Lakers shirt seemed genuinely excited — Kobe Bryant beamed, Steve Blake grinned and D’Antoni actually let out a little West Virginia howl — the most important guy in the room was genuinely cool.

D’Antoni’s first mandate is to win, but if he doesn’t keep Howard happy while doing it, everyone will lose.

“Is this fun?” said Howard somberly when asked about D’Antoni’s first loose practice. “Winning is fun, losing is never fun, we just have to find a way to win some games.”

Since showing up here this summer, Howard has always been the most jovial man in the room. But on Thursday, he was the most reserved. The guy who jumps every question would painfully pause before answers. There were more long faces than laughter. He was careful not to openly criticize, but he was also clearly not himself, and the reasons were as obvious as his blank stare.

Nobody on the team is affected more by the Lakers’ refusal to hire Phil Jackson than Howard. Nobody will have to make a bigger offensive adjustment to D’Antoni’s system than Howard. Nobody risks losing more offensive impact than Howard.

This matters because Howard is the only one of the team’s four superstars who can walk away this summer as a free agent. To lose him would be to lose the team’s future cornerstone. You think the organization appeared to crumble this week? If Howard walks next July, the collapse will be real, crashing sounds and ugly dust everywhere.

And thus the difficult wooing of a bulky superstar by a breakneck coach begins.

“His touches should increase, his ability to be able to get to the rim should increase, it should be a lot easier for Dwight,” said D’Antoni, diving into his first pitch shortly after uttering his first words. “If we can clear this off, clear some room, then he’s unstoppable. I expect Dwight Howard, as soon as he’s healthy, to be unstoppable. I don’t care what they do, they’re not stopping him.”

Three “unstoppables,” huh? Howard is going to have to believe that, and live it, to overcome doubts about the 782 games that D’Antoni has coached without every truly relying on — or exploiting — a big man.

D’Antoni is a point guard coach. He is a Steve Nash coach. He will be a Steve Blake and Chris Duhon coach. He was an Amare Stoudemire coach for several years with the Phoenix Suns and New York Knicks, and what did the 6-foot-11 dude do this summer to prepare for a season without him? He flew to Houston, to see former great center Hakeem Olajuwon and learn how to play the post. D’Antoni was actually a Shaquille O’Neal coach for 28 games once, and Shaq averaged 13 points and 11 rebounds, but it never really worked and the Suns were bounced from the 2008 playoffs in the first round.

Yeah, um, this is not Howard’s kind of offense, and he’s not above already mentioning one of its difficulties.

“The biggest thing is getting in shape so we can run,” Howard said. “We’ve got a lot of old guys and old legs on the team. I’m one of those guys.”

Howard knows that he will have to change. He knows he will not be Shaq in a triangle devised by Jackson. He will surely hear what D’Antoni told the media when he said, “One of the least efficient plays in basketball is the straight post-up, it’s just not efficient.”

However, D’Antoni was even selling Howard before he said that, noting, “I told Dwight today, he can be in every play, we don’t call plays, he can come down and pick the ball and go.”

D’Antoni knows what he needs most. He knows he needs Howard as much as former Lakers coaches needed Bryant. I asked Howard how he thought it would work. He didn’t smile, but at least this time, he didn’t pause.

“I’m going to do whatever I can to make this team better, to make him a better coach,” Howard said. “I’m fine if I’m supposed to score. If not, I’ll just go get it off the glass, there always ways to get buckets, not just somebody calling plays.”

And if he gets ignored amid all the running and gunning, and if the Lakers are losing because of it, well ...

“I do understand that sometimes I have to get fed now and then,” Howard said. “A big man should eat.”

Or, believe me, everybody around here will starve.

bill.plaschke@latimes.com