OAKLAND -- A's players found out they had a new teammate during the seventh inning of their Monday game against the Minnesota Twins when it was announced over the public address system. Before shortstop Adam Rosales stepped to the plate it was announced over the in-stadium speakers that Stephen Drew had been acquired by the Oakland Athletics from the Diamondbacks for Single-A infielder Sean Jamieson. Rosales popped out. This season A's shortstops are hitting an MLB-worst .187. Oakland had been actively trying to upgrade at the shortstop position. They finally got their man. Drew will be reporting to the A's on Tuesday and a corresponding roster move will be made prior to the game. "We've been looking for a few weeks since before the deadline to see if there was a chance to get this team some added help," A's assistant general manager David Forst said. "It worked out with the Diamondbacks because Stephen Drew was available." How much of an upgrade Drew actually is remains a huge question. Drew, 29, is batting .069 (2 for 29) in his last nine games. He is batting .193 in 40 games this season after returning from a fractured ankle sustained on July 20, 2011. He missed a total of 137 games with the injury."At times and certainly before his injury he was a pretty good offensive player," Forst said. "He's shown that occasionally since he's been back this year. Hopefully coming here gives him a little added boost and gives us a boost as well."Drew is a career .266 hitter with 72 home runs and 333 RBIs in 773 games. He has a .328 career on-base percentage. His best year was in 2008 when he batted .291 with 44 doubles, 11 triples, 21 homers, and 67 RBIs. He was named the Diamondbacks player of the year that season. His manager at the time was Bob Melvin. Melvin managed Arizona from 2005-2009. He didn't want to talk much about the addition of Drew after the team's 7-2 loss to the Twins. "I think in fairness to everyone in the clubhouse I'd prefer not to get into it too much," Melvin said. "I do know Stephen. He is a good player, he will be a good fit here and lets just kind of leave it at that."The A's had scouts watching Drew before and after the trade deadline. Forst says they feel good about what they know about Drew because Melvin and bench coach Chip Hale have a history with him. "Anytime you are trading for a player that you don't know it helps when you've had somebody that's been around him." Forst said. "He's struggled a little bit as of late, but we think that player is still in there."The A's will eat the remainder of Drew's 2012 salary. He has a mutual option for 2013 worth 10 million dollars and a 1.35 M opt-out clause. Forst says they will see how he performs for the remainder of the season before making any determinations about if they want to keep their new shortstop around in 2013. The timing of the move to acquire Drew came as a surprise to the A's players. Especially to the team's longest tenured shortstop Cliff Pennington. "He plays the same position, so I guess we'll see what happens," Pennington said. Pennington was reinstated from the disabled list on August 7. He is batting .207 in nine games since his return. The addition of Drew sends a message that the A's are attempting to upgrade. "Hopefully he is a guy that comes in and fits in well and helps us win," A's starting pitcher Brandon McCarthy said. "But I think we are past the point of needing a spark. We just need to keep playing well.""I guess they are trying to make a push," second baseman Jemile Weeks said. "They're trying to improve where they feel they need to improve."The way the move was announced and that it happened at this late stage of the season may caught the players slightly off guard, but they understand that baseball is a business.."It's like anything where there's a new person coming in," McCarthy said. "Something has to happen to somebody you know and like. That's never a fun thing. That's why you hope someone comes in and plays well right away and you sort of smooth that transition." The A's shortstop position has been a revolving door this season. They have started Pennington, Rosales, Eric Sogard, and Brandon Hicks at that position. Weeks has had to adjust to a lot of double play partners. He says he is ready to adjust to one more. "He's a good player," Weeks said. "If he comes along and fits in and helps us win we are all for it."