Andrew Bynum, Pau Gasol face life without Lamar Odom

Pau Gasol and Andrew Bynum stood back to back in front of a purple backdrop Sunday morning, the Lakers’ 7-footers clutching basketballs and smiling as cameras clicked during media day.

There was someone missing from the picture.

Lamar Odom is on his way to Dallas after being traded to the Mavericks the previous day, leaving Gasol and Bynum as the Lakers’ big men of the moment.

“That definitely affects us negatively, obviously,” Bynum said. “We had the best front line, I’d say, between me, [Odom] and Gasol, so I think it’s going to be a little different, the way the rotations are going to work this year, and I really don’t know what to expect.”

The Lakers’ roster seems to be changing by the minute, particularly when it comes to post players.

Gasol and Odom were thought to be gone Thursday night as part of a three-way trade involving New Orleans point guard Chris Paul before NBA Commissioner David Stern voided the deal.

Bynum’s name continues to be linked as part of a possible swap for Orlando center Dwight Howard.

Well, at least Derrick Caracter can probably count on starting the season as a Laker, unless he’s included in a trade package.

“Let’s see what happens the next few days and see where we’re at,” Gasol said.

The loss of Odom will deprive the Lakers of more than a versatile 6-10 forward who averaged 14.4 points and 8.7 rebounds last season on the way to winning NBA sixth man of the year.

Odom was also a galvanizing presence in the locker room, someone who players young and old gravitated toward.

“He was always somebody keeping the mood light, somebody you went to just to talk to and always had an honest opinion,” Bynum said. “Just a cool guy.”

The Lakers seemed particularly taken aback by the fact that Odom was traded to the team that knocked them out of the playoffs last season.

“That’s definitely not a good thing,” Bynum said. “I don’t understand it.”

Odom’s departure could leave the Lakers particularly short-handed in the frontcourt to start the season if no subsequent roster moves are made because Bynum is slated to serve a five-game suspension for committing a flagrant foul in the playoffs.

That would probably entail a smaller lineup and more minutes for the likes of forwards Matt Barnes, Luke Walton and Devin Ebanks. Assuming they’re still here, of course.

Bynum said Lakers General Manager Mitch Kupchak had not said anything in recent days to him or his agent about potential moves.

“I don’t know if that’s good or bad,” Bynum said.

Gasol acknowledged the emotional toll the last few days had taken was steep and sounded as if he was tired of the uncertainty.

“I want to have the security that whatever I’m a part of, I’m a part of that,” he said, “so I’m totally focused and committed to that and not wandering around.”

ben.bolch@latimes.com