Halfway to what?

The Wizards were exposed against Phoenix on Tuesday, haven’t corrected their flaws and are merely renting space at the top of the Eastern Conference until Detroit gets serious and Shaq rounds into shape in Miami.

What is known is Washington (24-17) is in first place in its division this late in the season for the first time since the 1978-79 season, also the last time the franchise won a division title.

At the midway point, here’s a look at four areas that spurred the first half and will also key the second:

» M-V-P: Gilbert Arenas says Steve Nash is the league MVP and, after Tuesday, it’s hard to argue. But Arenas is a strong candidate.

Already in the first half, he’s scored 50 or more points three times, hit two game-winning jumpers and is second in the league in scoring at 29.7 points per game.

He still needs to improve his on-the-ball defense. That would go a long way toward helping shore up the Wizards defensive woes in the paint.

» Antawn Jamison: When Jamison scores 20 or more points, the Wizards are 14-6. But when he scores 15 or fewer points, they’re 3-9.

Jamison has said he’s mentally fatigued from all the traveling he did this past summer in the World Championships only to have training camp start a month or so later. He’s not driving to the basket as often, one reason why he’s attempted just two free throws or less in 19 games. He needs to be mentally recharged.

» Healthy finish: It’s important for players such as Jarvis Hayes to contribute more or Darius Songaila to help at all to give Jamison more of a break.

Hayes is still finding his rhythm after missing 61 games last season, but how much will he improve? After all, he’s shooting 38.9 percent for the season; he’s only a 39.7 percent career shooter.

Songaila might play limited minutes when he returns, but he can still hit the open shot and play defense. And center Etan Thomas is still rounding into form after missing 13 games with an ankle injury.

» Tough Juice: Tough-minded forward Caron Butler has played like an All Star, averaging 21.1 points and 8.0 rebounds per game.

But if the Wizards are to be a postseason threat, they must rebound better. Right or wrong, that will partly fall on Butler, who is a solid offensive rebounder, but not as strong on the defensive glass. The Wizards are being outrebounded by nearly three boards a game; Butler has the strength and desire to narrow that gap.

Songaila returns to practice

Darius Songaila has spent his first season in Washington nursing a bad back, recovering from surgery and watching his teammates. On Wednesday, he finally got to do something fun: practice.

Songaila endured a full practice for the first time this season. Though there’s no timetable for his return — and he’s likely a couple weeks away at least — it’s yet another step in his recovery from November back surgery to repair a herniated disc.

“He played longer and more physical than I thought he would,” Wizards coach Eddie Jordan said.

The Wizards signed the 6-foot-8 Songaila for his defense, passing and ability to hit the 15-foot jumper. However, because of how much time he’s missed, and the fact that he hasn’t played with his teammates before, they don’t expect to see him at his best.

“He won’t be the real Darius until next year,” Jordan said.

Songaila missed the final 20 games of last season with Chicago because of a fractured foot. He hurt his back playing for his native Lithuania in the World Championships this summer.

“It’s been a tough year,” he said. “But all that is behind me.”

— John Keim