OAKLAND -- Right before the A's usual stretch time Tuesday, the starting lineup for the team's series opener against the visiting Phillies was missing.

When the lineup finally made its way out into the clubhouse, Mark Ellis' name that was missing.

According to manager Bob Geren, Ellis was feeling under the weather, but the skipper would not specify exactly what was wrong with his second baseman.

"He's available if necessary," Geren said. "If I need him, he'll come play. He's just not feeling real good."

Before Tuesday, Ellis had played in 66 of Oakland's 75 games. He had his sixth three-hit game of the year on Sunday, when he was also ejected for the first time in his career for arguing balls and strikes after striking out in the seventh inning.

Donnie Murphy was in the second-base slot with Ellis out, and Kurt Suzuki got the nod for batting in the leadoff position -- a role that Ellis had been filling.

"Kurt's swinging the bat well right now," Geren said. "It's just temporary until Mark feels better. He's done it before -- two factors right there."

While Geren had to keep Ellis out of the lineup Tuesday, the skipper was able to put Daric Barton back in. The A's first baseman, who had been nursing a strained right hamstring, sat out of Saturday's game against Florida and did not enter Sunday's game until the seventh inning, when Oakland needed an infielder in Ellis' absence.

"I'm feeling better," Barton said. "The leg's getting there."