Alex Rodriguez out Wednesday

NEW YORK -- New York Yankees third baseman Alex Rodriguez says his lingering left thumb injury is feeling "better" but not well enough for him to play in Wednesday night's 6-4 loss against the Oakland Athletics.

After taking ground balls and some swings in the batting cage, Rodriguez said that he would not be in the lineup against the A's.

"I'm feeling better today," Rodriguez said shortly before Tuesday's game. "Swelling has gone down quite a bit today. X-rays were good. We're hoping in the next day or two we're ready to go."

It is unclear before the game if Rodriguez would be available as a pinch hitter on Wednesday, but manager Joe Girardi never put him in.

Rodriguez also missed Tuesday's game due to the thumb ailment. He suffered the injury while backhanding a ground ball off the bat of Minnesota Twins catcher Joe Mauer on Sunday.

The Yankees said X-rays on Rodriguez's thumb taken Tuesday were negative, and he is listed as day to day to with a sprain.

Rodriguez was encouraged after taking ground balls on Wednesday evening.

"The good news is the glove went (on) today," he said. "Yesterday I couldn't even get it on. And the swelling's gone down quite a bit. It looked like a bee had bit me a couple days ago, so it's better."

Rodriguez took about 30 swings in the batting cage on Wednesday -- 15 off a tee and 15 during a toss drill. Afterward, he reported that his thumb felt "pretty sore" but improved from Tuesday.

On the bench Tuesday night, Rodriguez was wearing a large wrap. But Girardi said it was just precautionary and common practice for longtime Yankees trainer Gene Monahan.

Rodriguez returned to the Yankees' lineup on Sunday in Minnesota after missing more than a month and a half while on the disabled list with a knee injury. The 36-year-old All-Star went 0-for-5 in his return, but Girardi said he was impressed with A-Rod's progress.

Rodriguez, who suffered somewhat of a power outage due to problems associated with his surgically repaired hip earlier this season, is batting .290 with 13 home runs and 52 RBIs in 81 games.

Yankees general manager Brian Cashman said he was not concerned that his third baseman's latest injury would linger more than a few days.

"My trainers ... say it's just day to day and it should be resolved so hopefully that's the case," Cashman said.

Ian Begley is a regular contributor to ESPNNewYork.com.