AKLAND -- On the same day the A's got a key cog in their lineup back, they lost one in the bullpen.

Seth Smith was reinstated from the disabled list Tuesday and started the club's contest against the Twins at designated hitter, while lefty reliever Jordan Norberto was placed on the 15-day DL with left shoulder tendinitis.

It's the second time this year Norberto has been affected by the issue, having already missed time May 31 to June 20. Since then, he's posted a 1.69 ERA in 18 appearances with the A's, contributing to a 2.77 season mark spanning 39 outings.

Despite the loss of Norberto, the A's still have seven in their bullpen. He's eligible to return Sept. 2.

Smith, meanwhile, rejoins the team after making just one rehab start for Triple-A Sacramento, going 2-for-3 at DH on Monday night. He's batting .237 with 11 home runs and 39 RBIs for the A's this season.

Weeks optioned to Triple-A Sacramento

OAKLAND -- In an active offseason, the A's early on identified franchise cornerstone Jemile Weeks as their one and only untouchable player.

That he still might be, but he's not immune to a demotion, as he learned Tuesday afternoon.

With newly acquired shortstop Stephen Drew on his way to Oakland, Weeks was optioned to Triple-A Sacramento just one year removed from a remarkable rookie season. Hitting just .220 this year with the second-lowest slugging percentage in the American League at .305, the 25-year-old second baseman wasn't exactly stunned by the move.

"For some reason I feel like I was prepared for the news," said Weeks, sporting street clothes as his teammates dressed for the annual team photo. "It's disappointing, because I know I could have done more as a player. I still feel like I did a lot of things I wanted to do. The hitting part just wasn't there, and that's probably more of the reason why I'm going down."

"This will give him the opportunity to go down there and work on some things without the everyday pressure that you get at the big league level," manager Bob Melvin said. "Once you go through a season where you continue to struggle some, it can weigh on you, certainly mentally and physically. He hasn't performed to the level that we've gotten used to seeing in the last year, but that doesn't mean he won't have the type of career we expect him to have in this organization and that he expects himself to have. Sometimes these things can be a blessing in disguise."

Melvin will subsequently move forward with a platoon at second base, with Adam Rosales garnering the majority of starts against right-handers and Cliff Pennington -- no longer the go-to option at shortstop with Drew in tow -- getting starts with left-handers on the mound. Pennington has just 16 career games under his belt at second base, all coming in his 2008 rookie year, and 46 more to his name in the Minors.

Pennington was thought to be the more likely choice to be sent down Tuesday, what with Drew taking over his position in the midst of a disappointing offensive campaign that's resulted in a meek .198 average and .549 OPS. Being more seasoned could have given him the edge, though Melvin remained rather mum on the topic, only expanding when asked about his confidence in Pennington at a new position.

"We just think that he can," he said. "He's a good middle of the diamond defender. The one variable that he's not used to is turning the double play on the other side, even though we do shift quite a bit and he is over on that side. He takes ground balls every day and he'll turn double plays based on who is taking ground balls at shortstop. We think he has the defensive ability to pull that off."

Weeks, who hit .303 with 22 stolen bases in 97 games with the A's last year, could be back as soon as Sept. 1, when rosters expand. Between now and then, he'll seek consistency, all the while maintaining the same confidence he displayed when speaking to reporters Tuesday, telling them, "At the end of the day, I'm going to be a star in this game. You gotta have your ups and downs. It just makes the story so much sweeter when you come back. I don't wanna expound too much on it, but you're looking at a star, period.

"I think there have been times in big games where I've gotten hits, times where I've put together two or three hits, but it just hasn't been consistent," he said. "Until that consistency comes, you're in jeopardy of this happening. It's the game. It's anybody's job."

Drew joins team, makes start at shortstop

OAKLAND -- Only time will tell if Stephen Drew's offensive ability is greater than his current numbers suggest, but the only certainly at this point is that there's not much of it.

Just six weeks remain on the A's regular season calendar, and Drew's production during that span could help determine Oakland's fate in the standings. Acquired late Monday night from the D-backs, Drew's time with the A's began immediately, as he was inserted into the lineup batting second and playing shortstop Tuesday against the Twins.

It will mark just his 41st game of the season, having missed a lot of time because of an ankle injury he incurred last season. He enters his A's debut batting .193 -- but his talent level is much higher, he believes.

"I do, I really do, but that's just baseball," Drew said. "I know it's a numbers' game, but at the same time it's one of those things were you hit lineouts really hard and don't get the results you want. You wish it would fall for you.

"My thing is, I'm going to try to put good at-bats together. That's all you can do. You can't control where the ball goes. For me, I'm going to try to just produce good at-bats and play good defense and hopefully help get this team back into the race."

Drew is a career .266 hitter who enjoyed his best seasons under the tutelage of manager Bob Melvin, for whom he batted .291 with 21 home runs and 67 RBIs in 2008.

"He helps a team all the way around," Melvin said. "I know he's had some struggles this year, at least on the surface looking at the numbers. But I've seen this guy be an all-around player. He can defend, he swings the bat well, he drives the ball, he knocks in runs. He's a guy that can move around in the lineup. He's one of the shortstops around the league that everybody looks at and says this guy can be an impact guy, not only offensively but defensively as well."

With Drew now manning shortstop, former incumbent Cliff Pennington will shift -- temporarily, he hopes -- to second base, where he'll share duties with Adam Rosales, following Jemile Weeks' demotion.

"He would probably tell you that he's still a shortstop and I would want him to think that way, but right now his opportunity is at second base," Melvin said of Pennington. "Talking to him today, he understands that and he's going to work as hard as he can to be a very good second baseman."

Drew, meanwhile, will wear No. 5, the number that his Triple-A manager and current A's bench coach Chip Hale previously donned. Hale now sports No. 8, which Kurt Suzuki wore before his trade to Washington.

"This is a good start for me, a good fresh start," Drew said. "I'm happy to be here. Hopefully I can help this team win.

"I feel 100 percent. I feel really good. With that injury, I didn't know where I was going to be, and working really hard in the offseason and getting it really healthy, I feel really good where I'm at now. My range has gotten back to where it needs to be here at short, and I feel like it's back to normal."

Worth noting

• To clear a space on the 40-man roster for shortstop Stephen Drew, the A's on Tuesday designated right-hander Graham Godfrey for assignment.

Godfrey was on the A's Opening Day roster and went 0-4 with a 6.43 ERA in five games -- four starts -- over two stints with Oakland. He had been with Triple-A Sacramento since May 27, posting a 9-2 record and 3.29 ERA in 20 games (17 starts) with the River Cats.

The A's have 10 days to trade, release or pass him through waivers.