Did the Phillies Overpay for Placido Polanco?

It looks like the Phillies have found their starting third baseman. Welcome aboard, Placido Polanco:

"According to multiple sources familiar with the club's thinking, the two sides are closing in on a three-year, $18 million deal, pending a physical.

The 34-year-old infielder arrived in Philadelphia on Thursday morning to take that physical, and told NBC-10 TV's John Clark that he's "excited to join a championship team."

Before Wednesday, the Phillies appeared to be locked in on three potential free-agent third basemen -- Polanco, Adrian Beltre and Mark DeRosa. But talks intensified with Polanco's agents Wednesday, a day after his old team, the Tigers, declined to offer him arbitration."

I understand why the Phillies went after Polanco and I actually think he's a nice addition to their lineup. He's a solid #2 hitter, who can hit for average, put the ball in play, and hit for some power (10 HR, 30 2B). Remember that in the three seasons prior to 2009, Polanco's batting average never dipped below .300 and he even hit .341 in 2007. From that perspective, I think the Phillies made the right move making a play for Polanco.

However, I'm very skeptical about giving Polanco a three year deal because there is a good amount of risk involved here. Polanco is 34 years old and by the time the contract expires he will be 37, which is a risk given how many players' skills diminish as they get older. Also, we have to wonder about how well Polanco will be able to man the hot corner. The benefit of having Pedro Feliz over the past two years was that his defense was spectacular. Can the Phillies expect Polanco to be the same type of defender as Feliz? Absolutely not. I think the Phillies expect Polanco to be an average to above average fielder, but because Polanco has not played the position in any capacity since 2005.

This deal could turn out great for the Phillies in 2010 and even 2011, but I'm nervous to see how a 36 year old Polanco can perform at third base everyday for the Phillies in 2012.
***Was this a smart signing for the Phillies?***