Clayton Kershaw’s maturity level continues to rise

He’s been smart, funny and full of promise from the very start, a teenager babied in his baseball development who is now 23, recently married and about to become a full-fledged star.

He’s a Dodger, and the Dodgers don’t have many stars. Clayton Kershaw, though, is the brightest of them all.

He will be the team’s opening-day pitcher against the defending World Series champion Giants and matched against Tim Lincecum.

No more baby steps.

“I expect to do well; that’s not being cocky or anything,” Kershaw says, “but at this point I have to keep progressing. If you don’t, you get left behind.

“Now I’m not going to try and down play that I get to pitch opening day. I think that’s a sign of recognition from your manager and with that comes expectations. I’m looking forward to living up to those expectations.”

Marcus Thames can’t field, can’t hit righties, won’t talk about it . . . are you excited yet?

There has always been an air of sensibility and confidence about Kershaw, as well as a hint of greatness that comes from watching his curveball freeze some of the game’s top hitters.

Some of the media who cover the Dodgers on a daily basis say they have detected a change in Kershaw. He didn’t like something someone wrote, and Page 2 is innocent in this case, and came to the media room to confront the reporter.

Others wonder whether the pressure of becoming one of the few marketable players the Dodgers have on their roster is taking its toll in terms of his time and temperament.

He says he’s no different, and welcomes the attention.

“It just means that people recognize what you might be able to do as a competitor,” he says. Every player should be as obliging and friendly as he has consistently been over the years.

At this stage of his development on the field, meanwhile, the best chance opponents have of beating Kershaw now is Kershaw beating himself.

“That’s got to be my mentality — don’t walk people,” Kershaw says. “If you throw strikes you’re putting the pressure on them. It sounds easy, but something that still doesn’t come easy for me.”

L.A. Times Dodgers blog

The Dodgers don’t have much box-office sizzle this year unless Rod Barajas does it for you. Andre Ethier has shown All-Star ability, and Matt Kemp has the talent to be one of the game’s top players if his personality allows it.

If only Kershaw could pitch every day, then there really would be a reason to watch this team play. The other four days, well, I guess there’s Barajas.

MARCUS THAMES, pronounced “Tims/Tems,” ran past me carrying a first baseman’s glove. I guess the Dodgers don’t want him to hurt himself, so they took away his outfield glove.

“Come on and help me out,” he says with a laugh.

He caught the first eight out of 10 ground balls at first, the next 11 straight and I guess the Dodgers will be moving James Loney to left field.

“So go ahead and ask me the question you wanted to ask,” says Thames, as friendly as his teammates had described him before walking off in a snit a day earlier.

“Are you that horrible on defense that teams don’t think it’s worth playing such a home run threat?”

“No, I’m not that bad of a defensive player,” he says, and that wasn’t so tough, now was it?

“When I first got to the big leagues I was labeled a DH,” he says, so why would the Dodgers hire a DH?

“They’re not getting a DH,” he says. “If I can get out there on a more consistent basis, I can prove myself.”

The Dodgers are going to platoon Thames in left field with a cast of rejects because he also has the reputation for not being able to hit right-handed pitchers.

“Certain righties,” he says. “I’m a better hitter against right-handers than people think.”

Now as for running away from the obvious question a day earlier, Thames says, “I didn’t handle it well because I’ve never been approached the way I was approached. It shocked the hell out of me.”

I found it odd that over the last nine years that no one had asked him about his poor defense keeping him from becoming an everyday player.

“I heard talk, but no one had ever said it directly to me,” he says, understandably thrilled now to have it said to his face rather than behind his back.

Just took him 24 hours to be thrilled. That’s all.

MANAGER DON Mattingly was asked whether Dodgers fans deserve better than the roster of players assembled.

“We’re going to have a good club,” he says. “We’re going to have five guys [pitching] — every time they walk out there they are going to give us a chance to win. We’re going to have a lineup that gives us a chance to put some runs on the board, we’re working hard and we’ve got some talent here.”

Advised that he was “nuts,” he says, “You know what? I’m excited about the year. I think we’re going to have a good year. Dodger fans are going to like the club they see.”

A third-place finish would be better than last year.

AS YOU might imagine, the Dodgers are getting very excited about the start of the season, and are especially looking forward to April 15.

That’s when Frank McCourt is obligated to start paying them. If he can.

AT THE morning news briefing, broadcaster Eric Collins looked at Mattingly and said, “Skip, who’s throwing today?” At least he didn’t say, “Who’s on the bump today?”

Anyway, no one had the heart to tell him Mattingly’s first name is “Don,” and not “Skip,” and that he could have found the name of the starting pitcher on the wall in the clubhouse where it is every day.

Even Charley Steiner knows that.

t.j.simers@latimes.com