MESA, Ariz. -- Lou Piniella wasn't ready to name his Opening Day starter with more than one month to go in Spring Training, but Carlos Zambrano looked like he was ready in his first Cactus League outing.

Zambrano struck out three of the six batters he faced in two innings of the Cubs' 9-1 loss to the Arizona Diamondbacks on Monday in front of 9,605 at HoHoKam Park.

"We don't have one yet, we really don't," Piniella said before the game when asked if he had picked an Opening Day starter. "First of all, let's stretch everybody out and see where everybody is by the middle of March. You'll see who the pitcher is by how we set the schedule. You can look two weeks in advance.

"Right now, I think it's too early for that. I'd say it'll either be Zambrano or [Ryan] Dempster."

Zambrano has been the Opening Day starter four years in a row, the most by a Cubs pitcher since Rick Sutcliffe started five consecutive season openers from 1985-89.

"I've been the Opening Day starter," Zambrano said. "Dempster had a good year last year and he deserves it."

Zambrano is coming off a 14-6 season, which included his first no-hitter, while Dempster was 17-6 with a 2.96 ERA in 33 starts. Piniella did say Ted Lilly would be the third starter, followed by Rich Harden.

"We'll see what we do in the five-hole," he said.

Zambrano is just thinking about what he'll do five days from now.

"I liked everything I threw today," he said of his outing. "So far, to be my first outing since the playoffs, face Major League hitters, it was pretty good."

The Cubs have given Zambrano a little more time this spring and not rushed him. It looked liked the rest paid off.

"With that kind of stuff, you'll have a pretty good chance to go out and compete and win a baseball game," Piniella said. "The key is to stay focused and work hard."

He's a leaner, trimmer Big Z, which should result in a quicker fastball.

"I lost some weight and my fastball is back," Zambrano said. "I lost like 15 pounds, 10 pounds. I have to still work hard. It's not that I wasn't in shape, but I want to be in [better] shape and ready to go."

Carlos Marmol followed Zambrano and struck out two of the three batters he faced. Marmol will leave Arizona on Tuesday to join the Dominican Republic team and prepare for the World Baseball Classic.

What if he has to face Cubs teammate Geovany Soto, who is playing for Puerto Rico?

"I'm going to strike him out," Marmol said with a smile. "I'm going to try. He'll be the enemy out there."

The right-hander lost some sleep trying to decide whether he would play in the World Baseball Classic. He worried that he would miss the opportunity to compete for the Cubs' closer job. Piniella has assured him that the competition will be on hold until Marmol returns.

"I feel more comfortable, good," Marmol said. "I'm going to represent the Dominican team, my country. I feel good."