"We'll see how he does and give him a chance," said manager Bob Geren, who wasted no time in putting Pennington in the lineup -- where he played third base.
To clear a spot on the 40-man roster for the A's first pick in the 2005 First-Year Player Draft, 21st overall, Oakland designated infielder Brooks Conrad for assignment. The move followed a 10-game road trip during which the A's went 1-9 -- and third baseman Jack Hannahan went 2-for-36, giving the A's reason to take a close look at Pennington.
The 24-year-old was batting a combined .280 with two home runs, 34 RBIs, 31 stolen bases and a .404 on-base percentage in 115 games with Double-A Midland and Sacramento. Even more, he was leading the Minor Leagues with 93 walks and was tied for sixth with 89 runs scored at the time of his promotion.
"I'll just be sticking with the same thing that's worked all year," Pennington said of his hitting technique in the A's clubhouse before batting practice. "Sometimes they fall, sometimes they don't. Lately they've been falling."
The switch-hitter appeared in 80 Minor League games at shortstop, 32 at second base and three at third base this year. Geren, however, expressed much confidence in the newcomer's ability to make plays at the hot corner.
"It's not his No. 1 position right now," the skipper said, "but this is an opportunity to get him in the lineup."
That's just fine by Pennington, who learned of his promotion Monday night -- just enough time to get his mother and wife to Oakland to be present for his Major League debut.
The infielder wasn't the only A's player making his home debut, though. Pennington was looking forward to playing alongside Gio Gonzalez, Tuesday's starting pitcher.
"It's a good thing," Pennington said of having a familiar face on the field. "I've got a few games behind him already."
The rookie's promotion, though, meant a demotion for DiNardo, who enters his second stint of the season with Sacramento. The relief pitcher suffered a nightmarish eighth inning Saturday night, allowing five hits and four runs (three earned) against the Tigers. Overall, he was 1-2 with a 7.43 ERA in 11 outings this year.
The transaction forced Geren and his crew to appoint Dan Meyer as the team's new long man. The southpaw gave the A's five solid innings of work against Detroit on Saturday while making a spot start for the injured Sean Gallagher.
"I thought Meyer's been pitching really well," Geren said, "so I decided to go with him. But I feel confident with both pitchers."