If Piniella sticks to his plan, the Cubs' lineup on Opening Day against the Atlanta Braves would be Theriot, Fukudome, then Derrek Lee, Aramis Ramirez, Marlon Byrd, Soriano, whoever wins the second-base job and Geovany Soto.
"As we speak, Fontenot has jumped ahead on the second-base side," Piniella said. "It hasn't been finalized, but that's the way I view it."
Fontenot started last season as the Opening Day second baseman but struggled, batting .236. He began camp battling Jeff Baker for regular playing time.
"However it plays out, we have a lot of good players," Theriot said. "A little competition is always good, and I think it's something we've lacked the last few years. It brings out the best in everybody. When the game starts, we're one unit. We wear the same uniform and we want the same things and that's to win ballgames, whether it's hitting first or hitting eighth."
Theriot has had a little competition, at least in the hype department. Young shortstop Starlin Castro, who will open the season in the Minor Leagues, has gotten most of the attention.
"Every Spring Training, I come in and feel like I'm prepared," Theriot said. "All you can do is go out there and get hits and play good. We'll see what happens. You never know."
Theriot was batting .550 this spring after going 1-for-3 on Monday in the Cubs' last trip to Hi Corbett Field. He's made some changes with his swing, thanks to new hitting coach Rudy Jaramillo.
"I think I'm enjoying the benefits of that right now," Theriot said. "I'm excited to see where it goes."
If Fontenot is the starter, that would give the Cubs two left-handers in the lineup in him and Fukudome.
"As long as the lefties in the two and seven holes hit, that's the important thing," Piniella said.
The Cubs still want Fontenot to play at shortstop this spring to see if he can back up there. If so, the team might consider keeping someone like Chad Tracy or Kevin Millar on the bench for more offense. Millar, who started at first base on Monday, will likely play some left field in spring.
Lee and Ramirez both missed the Cubs' trip to Tucson, and neither was expected back in the lineup until after Wednesday's off-day. Lee has been sidelined with a bruised left foot and Ramirez has a sore right triceps muscle. Ramirez asked to be the designated hitter on Tuesday when the Cubs play host to the Texas Rangers but Piniella said he'd like to get Xavier Nady those at-bats.